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1
Silencing of BCL-2 Gene in vitro Environment by Transferring siRNA with Positively Charged
Nanoparticle to Breast Cancer Cell Line MDA-MB-231
C. C. Coban1, V. Karakoc2, A. C. Keskin1, M. Turk3*
1Kirikkale University, Faculty of Science & Arts, Department of Biology, 06450, Kirikkale, Turkey 2Nigerian Türkish Nile University, Department of Chemistry, Abuja, Nigeria
3Kirikkale University, Engineering Faculty, Department of Bioengineering , 06450, Kirikkale, Turkey
Cancer is a significant public health problem in a great deal of the world. In many cases the survival rate
is low in which delayed diagnosis or repeated cancer diseases. Gene therapy which is the new technology
can be defined to aim the treatment of gene disorder provoking the existing illness intentionally
transferring a specific DNA to another cell. RNAi is a mechanism to be using small RNA molecules,
providing to be silenced a specific gene and via triggering for instance the cell which encoding a harmful
protein. In this study, preventing of the synthesis of harmful protein by silencing of the interest of gene
for treatment of breast cancer is targeted. HEMA-based nanoparticles with siRNA are transferred to MDA-
MB -231 breast cancer cell line for inhibiting the expression of BCL-2 gene and increase apoptosis. In the
first section potential and size of the nanoparticles in the zeta-sizer device was measured, after that,
siRNA-loaded nanoparticles loaded on gel-electrophoresis was checked that it retains. In the second part
of the study siRNA- loaded nanoparticles attached on the MDA MB -231 of breast cancer cell line have
examined the effects on cancer cells. RTCA life index of the cells were measured. Apoptotic-necrotic
pathway of dying cells for determining which of the select, the cells are analyzed by fluorescence
microscopy after staining. The obtained results, BCL-2 gene is inhibiting by siRNA-loaded nanoparticles
and breast cancer cells was found to effectively stop proliferation.
2
Carbon Nanotube-Chitosan Based Graphite Electrode for Electrochemical Detection of
Anticancer Drug-DNA Intraction
C. B. Sengiz, E. Eksin, G. Congur, A. Erdem*
Ege University, Faculty of Pharmacy, Analytical Chemistry Department, Bornova, 35100, Izmir, Turkey
Analysis of interfacial biomolecular interaction mechanisms of drugs with DNA has been among the most
important topics of pharmaceutical studies in clinical analysis and drug design. Mitomycin C (MC) is an
antibiotic drug, which is used in clinical anticancer chemotherapy. MC can interact with nucleic acid by
binding to DNA bases and also prevent DNA replication and transcription. In our study, the
electrochemical detection of interaction between MC and double stranded DNA (dsDNA) was investigated
at the surface of disposable chitosan-carbon nanotube modified pencil graphite electrode (CNT-
CHIT/PGE). Electrochemical characterization of these electrodes performed by cyclic voltammetry (CV)
technique. The oxidation signals of MC and guanine were measured before and after the MC-DNA
interaction by using differential pulse voltammetry (DPV). Moreover, the electrochemical impedance
spectroscopy (EIS) technique was utilized for the monitoring of the interaction process at the surface of
CNT-CHIT/PGEs. The experimental parameters, e.g., the concentration of CNT, CHIT, DNA and MC, DNA
immobilization time and MC-DNA interaction time were also optimized for the development of CNT-
CHIT/PGEs, that were used furtherly for DNA and drug analysis. The CNT-CHIT/PGEs were developed for
the first time in our study for electrochemical monitoring of interaction of MC with DNA. The results
indicated that the CNT-CHIT matrix can be used for modification of the stable and sensitive sensor
platform for advanced monitoring of drug-nucleic acid interaction without using any time consuming
modification steps.
3
Cells Encapsulation and Printing
C. Migliaresi1, N. Cagol1, L. Gasperini1, 2, V. Liaudanskaya1, D. Maniglio1, A. Motta1
1University of Trento, Department of Industrial Engineering and Biotech Research Center, Trento, Italy 2University of Minho, 3B’s Research Group, Braga, Portugal
The presentation deals with the encapsulation of cell by using an electrohydrodynamic process and with
the effect of the processing on cells viability and metabolic expression. The electrohydrodynamic process,
also named “electrospraying” consists in the production of spheres of material loaded with cells starting
from a suspension of cells in a polymer solution. The suspension is ejected from a positively charged
metallic needle thanks to the electrostatic repulsion that is generated at the surface when it overcomes
the surface tension at the apex of the liquid cone, so leading to its disintegration and jetting towards the
negatively charged target. The activity falls in the area named “Organ printing or Bioprinting” that consists
in the layer-by-layer assembly of tissue spheroids as building blocks of in vitro regenerated tissues and
organs. Alginate has been used as encapsulating material that has been crosslinked by precipitation in a
calcium chloride enriched medium or by deposition (writing) on a gelatin substrate containing calcium,
with a sol-gel transition at 35 °C. The process parameters have been optimized as a function of the optimal
beads diameter in order to allow diffusion in/out of nutrients and waste products and to allow long term
viability of the encapsulated cells. The effect of the entrapment on cells metabolic activity has been
investigated by gene expression analysis of proteins markers associated with the stress induced on cells
by the process and with their ability to recover from it after release in culture dishes. The above data will
be discussed and preliminary results dealing with the production of cells containing 3D structures will be
also presented.
4
Constructing Tissue Regeneration Scaffolds Using Marine Biomolecules
M. Illsley1, A. Blunden1, L. Sauer1, C. Bowyer1, S. Colliec-Jouault2, P. Dubruel3, B. Thollas4, I. U. Allan*1
1University of Brighton, School ofPharmacy and Biomolecular Sciences, Brighton, UK 2Ifremer, Plouzané, France
3University of Gent, Department of organic Chemistry, Polymer Chemistry and Biomaterials, Gent, Belgium 4Polymeris
Severe burn injuries pose an immediate threat to life. The wound must be covered to prevent dehydration
and infection of the affected area. Following these critical measures, implantation of dermal regeneration
scaffolds following debridement of the wound site has become an accepted means of regenerating the
lost dermal tissue at the site of insult. Current dermal tissue regeneration matrices are expensive and are
generally derived from mammalian tissue, a process which carries a small risk of prion transmission to the
patient. We have been examining the use of fish gelatin and agarose as naturally gelling materials of
marine origin as alternative ingredients in dermal tissue regeneration scaffolds. By formulating these
materials into cryogels we have produced highly macroporous, morphologically uniform and elastic
materials with a potential to rival current gold standard commercial alternatives. A range of gel
formulations with varying degrees of cross-linking were examined for their rheological properties. The
most favoured formulation was assessed for its ability to accommodate the attachment and proliferation
of human dermal fibroblasts in cell culture over a 28 day period. Confocal laser scanning microscopy
revealed a great increase in cell numbers present within the scaffolds during the incubation period.
Cryogel formulations containing cross-linked fish gelatin and agarose show promise as dermal tissue
replacement materials.
5
Development of Arginine Containing Well-Defined Polymers and
Investigation of Complexation with DNA
D. Taykoz 1, V. Bulmus1,2
1Izmir Institute of Technology, Department of Chemical Engineering and 2Biotechnology and Bioengineering
Graduate Program, Urla, Izmir, Turkey
[email protected]; [email protected]
Cell-penetrating peptides (CPPs) have been widely used for intracellular delivery of nucleic acid
therapeutics. It has been shown that arginine richness improves the transfection efficiency of CPPs [1].
Inspired by arginine containing CPPs, we intended to synthesize arginine containing, well-defined
polymers and investigate the potential use of these polymers as nucleic acid carriers. Pentafluorophenyl
methacrylate (PFMA) was used to produce polymers having active groups available for efficient
modification with arginine. Reversible-addition fragmentation chain transfer (RAFT) polymerization was
used to produce well-defined polymers as it is one of the most amenable techniques to the synthesis of
polymers for drug delivery applications. RAFT polymerization of PFMA was performed by varying
polymerization conditions such as feed composition or polymerization temperature. Linear increase in
ln[M]0/[M] with polymerization time, and number average molecular weight (Mn) with monomer
conversion indicated RAFT-controlled mechanism of PFMA polymerization. P(PFMA) was reacted with
arginine methylester (AME) in the presence of triethylamine (TEA) at a polymer/AME/TEA mole ratio of
1/1/3. All active ester groups on the polymer were modified with arginine as determined by 1H- and 19F-
NMR spectroscopy. The AME modified polymers were complexed with a 700-bp DNA fragment at varying
guanidine/phosphate (G/P) group ratios. Gel electrophoresis experiments revealed that AME-modified
P(PFMA) was able to efficiently complex with DNA. The hydrodynamic diameter of polymer/DNA
complexes in PBS was found to be 500 nm, indicating aggregation tendency of the complexes.
Furthermore, P(PFMA) was copolymerized with poly(ethylene glycol) methacrylate (PEGMA) monomer to
form P(PFMA)-b-P(PEGMA). Modification of the block copolymers with AME, complexation with DNA,
cellular uptake and intracellular distribution are currently under investigation in our laboratory.
6
Novel Polymeric Endovascular Devices: Design and Performance
D. Cohn, R. Abbas, F. Widlan, M. Zarek, R. Malal, A. Bloom*
The Hebrew University of Jerusalem, Institute of Chemistry, Jerusalem, Israel
* Hadassah University Medical Center, Vascular and Interventional Radiology, Jerusalem, Israel
The formation of aneurysms is an extremely dangerous degenerative pathology of arterial tissues,
especially common in adult and elderly populations, whereby the wall of the artery weakens locally and
largely expands. In more than 80% of the cases, the rupture of the aneurysmal sac is fatal. An endograft
consisting of a vascular prosthesis mounted on a stent and deployed intra-luminally at the aneurysmal
site using a balloon, called EndoVascular Aneurysm Repair (EVAR), was implanted in 1991 for the first
time. Unfortunately, though, important drawbacks restrict significantly the use of these devices, mainly,
the occurrence of renewed blood leakage into the aneurysmal sac (endoleaks), despite the presence of
the endograft, and its gradual migration downstream. This lecture will introduce a polymeric device for
AAA treatment that will be deployed intra-luminally and then expanded at the aneurismal site so it tightly
attaches to the aorta, proximally and distally to the aneurysm. The implantation of these devices is divided
into two parts: {a} the insertion through the iliac artery, the navigation to the site and the expansion
stages, during which the flexibility of the device is critical, and {b} its long-term performance at the
aneurismal site, where the device is required to display appropriate mechanical properties and
satisfactory blood compatibility. The required stiffness differential was achieved following two strategies.
The first is based on thermally softening and stiffening the device, using a balloon filled with warm or cold
saline, at the different stages of the implantation. The second strategy generated endografts consisting of
an Expandable Component (EC) and a “Smart” Component (SC), with the latter being present within the
former. The EC is responsible for the large change in dimensions the endograft undergoes during its
deployment at the aneurysm. The SC is a low molecular weight, polymerizable or crosslinkable precursor
that fulfills two different roles: {a} It acts as a plasticizer during the early stages of the procedure
(navigation and expansion), rendering it with the required flexibility, and, {b} It stiffens the device after its
expansion and snug attachment to the vessel wall, once it polymerizes or crosslinks, imparting to the
endograft the necessary mechanical properties. Following the basic working concept of this study, various
expandable conduits were generated, differing in their composition, the technique used to produce them,
their mechanical properties and expandability ratio. The large expandability of these devices was
demonstrated in cadaveric pig aorta sections using a balloon filled with warm saline. The diameter of the
conduits increased more than three times and they became tightly attached to the luminal surface of the
vessel. The in vivo Proof of Principle of these devices, namely their ability to be deployed and inflated at
the site following minimally invasive procedures that are routinely used in the clinic, and generate a stable
and safe conduit, was demonstrated acutely in the abdominal aorta of pigs. Hybrid structures composed
of natural and synthetic polymers are widely utilized in tissue engineering applications since the
advantages of both are combined without the disadvantages of neither [1]. However, even though these
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hybrid structures support the cell adhesion and/or proliferation at a certain level, research towards the
improvement of surface functionality and nanotopography is essential. Therefore, this study focused on
the improvement of the surface functionality and nanotopography of the layer by layer electrospun 3D
poly-ε-caprolactone/chitosan/poly-ε-caprolactone hybrid tissue scaffolds by means of atmospheric
pressure plasma method. Two different atmospheric pressure plasma systems (nozzle type and dielectric
barrier discharge (DBD) type) were used for formation/creation of the functional hydroxyl and amine
groups and topographical changes on the surfaces of scaffolds and the modifications were carried out
under different gas medium (air, Ar+O2, Ar+N2). The changes in surface hydrophilicity were monitored by
using contact angle measurements in order to optimize the modification time and distance for the nozzle
type plasma system and the modification time and the gas flow rate for DBD type plasma system.
Additionally, the topographical and chemical characterizations of these modified surfaces were carried
out with SEM and ESCA, respectively. Both nozzle type plasma and DBD plasma were found to cause
nanotopographical and functionality changes on the surfaces of the layer by layer electrospun tissue
scaffolds, however, the shelf life study results indicated that the hydrophilicity introduced to the surfaces
was mainly because of the functionality changes. In conclusion, the samples treated with nozzle type air
plasma for 9 minutes from a distance of 17 cm and the samples treated with Ar+O2 DBD plasma for 1
minute under 70 cm3/min O2 flow rate were found to have the highest hydrophilicity compared to the
untreated samples. In the future, the topographical changes in individual fibers and cell-interaction
performance of the material will be investigated with AFM imaging and skin fibroblast cell line,
respectively.
8
Structural Design and Functional Modification of Vascular Grafts
Z. Wang, M. Zhu, K. Wang, L. Wang, Q. Zhao, D. Kong*
Nankai University, Ministry of Education, The Key Laboratory of Bioactive Materials, Tianjin 300071, China. *
Electrospun poly(ε-caprolactone)(PCL) vascular graft has been evaluated in long-term rat
abdominal aorta implantation by Walpoth’s group [1]. Although PCL grafts showed excellent
patency and little neointimal formation, the compact fibrous structure and low compliancy of the
PCL material resulted in reduced capillary density and notable calcification in the graft wall 12
month after implantation. A recent work from Wang’s group [2] demonstrated that
interconnected macroporous structure, rapid degradation and elasticity of the material are the
key factors for successful vascular grafts. In order to enhance vascular smooth muscle
regeneration, we have been focusing on the structural design of PCL-based vascular grafts. First,
a 3-layered porogenic tubular PCL graft with large pores (30-50 μm) in the middle layer was
prepared by electrospinning of PCL and co-electrospraying of PEO. Enhanced cell infiltration,
smooth muscle cell migration, capillary formation and extra cellular matrix (ECM) production
were observed in the porogenic scaffolds [3]. It was reported that optimal tissue regeneration
including vascularization, minimal immune responses and increased M2 macrophage infiltration
were observed when the pore size of the graft was between 30-40 μm [4]. Thus, we optimized
the fiber thickness and pore size of the electrospun PCL grafts. We found that if the diameter of
fibers was increased to about 6 μm, the average pore size of the graft could be increased up to
40.88 ± 13.67 μm. Such grafts showed excellent patency, cell infiltration and vascular smooth
muscle regeneration in rat abdominal aorta implantation. The special porous structure tended to
regulate macrophage into an M2 phenotype, which is important for vascular regeneration [5]. In
summary, electrospun PCL grafts with thicker fibers and larger pores demonstrated much better
cell infiltration, smooth muscle cells regeneration, and vascularization than the regular dense
electrospun PCL grafts. The migration and function of M2 macrophages which were controlled
by the pore size of graft played important role in vascular regeneration.
9
Self-Assembled Nanostructures Obtained at The Air-Water Interface: Mechanism,
Characterization and Their Application as Template to form Organic-Inorganic Hybrid
Nanostructures
D. Senyurek1, N. Aydogan1*
1 Hacettepe University, Chemical Engineering Department, Beytepe, 06800, Ankara, Turkey
In parallel with developments in the field of nanotechnology, self assembly of molecules has become a
very interesting subject. A variety of nanostructures can be obtained by self assembly which is driven by
noncovalent, secondary interactions such as hydrofobic interactions , π-π stacking etc.. The resulting
nano-sized particles, strips, sheets, tubes may be used effectively in biotechnological applications such as
microchips and biosensors. The molecules that are able to produce self-assembled systems are mostly in
the form of amphiphilic structure. The interfacial properties of these molecules needs to be studied in
addition to their solution properties. Medium sensitive functional groups of amphiphilic molecules
differentiate nanostructures to be formed at the interface. In this study, various concentrations of the
anionic surfactant (C14H8O2-NH-(CH2)10COOH) (Aqua) which is synthesized by our research group is used.
Aqua includes carboxylic acid group which is pH sensitive. Thus the interfacial behaviour of this molecule
can change with the pH of medium. In experimental section, Aqua was spread on different aqueous salt
solutions in Langmuir Trough and different types of self assembled nanostructures were obtained.
According to the results that are obtained from the characterization of these structures, it is seen that this
unique surfactant is capable of forming ribbon-shaped nanostructures of various lengths depending on
both the types of salts utilized in the subphase and the surface excess concentration of Aqua.
10
Detection of Electrochemical Behaviour of E.Coli K12: Degradation of
Pure and Crude Glycerol as Case Study
E. Karatas, D. S. Ozden and E. Piskin*
Hacettepe University, Chemical Engineering Department and Bioengineering Division, Center for
Bioengineering and Biyomedtek/Nanobiyomedtek, Beytepe, 06800, Ankara, Turkey
The Sharply growth of the biodiesel industry has created a surplus of glycerol that has generated
environmental concerns associated with contaminated glycerol disposal. Anaerobic digestion is an
attractive waste treatment practice in which both pollution control and energy recovery can be achieved.
In this study, degradation of pure and crude glycerol by E.coli K12 culture was examined. E.coli K12 was
grown up in minimal medium which contains pure glycerol, during 48 hours growing of E.Coli K12 was
detected by UV spectroscopy method at OD600 nm and growth curve was drawn. After 48 hours, glycerol
concentration was analyzed by HPLC. Afterward E.Coli K12 was cultured in minimal medium contained
crude glycerol and it is detected that E.Coli K12 consumed crude glycerol and grown up in aerobic
conditions. There is no toxic effect of crude glycerol for E.Coli K12 growing in minimal medium.
Experimental set up was made of tree electrode system with a potentiostat to see potential difference
while E.Coli K12 was growing in medium by giving certain amount of current. As a result, degradation of
waste glycerol was followed via potential difference and applying current made bacteria more attractive
to consume waste glycerol.
11
Gold Coated Magnetite Nanoparticles Mediated p53-GFP Transfection in Colon Cancer Cells
D. D. Usta1, M. Turk2 and E. Piskin1*
1Hacettepe University, Department of Chemical Engineering and Bioengineering Division, Centre for
Bioengineering and Biyomedtek/Nanobiyomedtek, Beytepe, 06800, Ankara, Turkey. 2Kırıkkale University, Department of Bioengineeering, Kırıkkale, Turkey.
Nowadays, cancer is a major cause of mortality. There are several problems about detection and
treatment of cancer. Gene therapy is a promising method to resolve this problems. Considering all these,
we synthesized functionalized magnetic nanoparticles-mediated p53 gene transfection (tumor suppressor
gene) into colorectal cancer cells (DLD-1). Magnetite nanoparticles (MNPs) were synthesized with polyol
process. A silica shell coating onto magnetite nanoparticles (Si@MNPs) was carried out by Stöber method
to functionalize the surface of particles and protect from agglomeration. In addition, Si@MNPs were
amine activated by APTES and then attachment of gold nanoparticles (Au@Si@MNPs) were carried out
onto the Si@MNPs. Finally, to facilitate the transferring of negatively charged plasmid DNA into DLD-1
cancer cells, Au@Si@MNPs were modified by cystamine. The obtained nanoparticles were characterized
by FTIR, TEM and XRD analyses. The Au@Si@MNPs had an average size of 100-200 nm. Au@Si@MNPs-
pDNA used for efficiently transfection systems. The purpose of this study is the optimazation of delivery
systems to realize an effective magnetofection into cancer cells. Furthermore, we investigated whether
expression of the delivered p53-GFP. For this reason, the quantification of p53-GFP mediated apoptosis
in DLD-1 cells were calculated.
12
Synthesis of Well-Defined Fatty Acid Polymers as Potential
Cell Membrane-Destablizing Agents
E. Aydinlioglu1, V. Bulmus1,2 1Izmir Institute of Technology, Biotechnology and Bioengineering Graduate Program and 2Department of Chemical
Engineering, Urla, Izmir, Turkey
[email protected]; [email protected]
Transfection vehicles are needed for delivery of biomacromolecular therapeutics to intracellular sites.
Bacteria and viruses have been efficiently used for intracellular delivery of genes and nucleic acids.
However they have potential immunogenic properties and safety concerns. Non-viral vectors including
amphiphilic peptides, cationic lipids and amphiphilic pH-sensitive polymers are attractive alternatives
because of their minimal toxicity and low immunogenicity. Among these vectors, lipid-based systems
show high transfection efficiencies. However, they can be problematic due to solubility and stability
problems. Polymer-based systems, although they are in general less effective in transfections compared
to lipids, are also highly promising for intracellular drug delivery as they can be easily endowed with
desired properties such as pH-responsive behavior and water-solubility, through versatile polymer
chemistry. To combine the transfection efficiency of lipid-based systems with versatility of synthetic
polymers, we intended to synthesize well-defined amphiphilic (co)polymers of a fatty acid as potential
components of intracellular drug delivery systems. While acidic group provides pH-responsive behavior,
long alkyl chain on the fatty acid may provide membrane-destabilizing activity. An unsaturated fatty acid,
10-undecenoic acid (UDA), was modified to form a methacrylate monomer (UDAMA). UDAMA was
copolymerized with methacrylic acid (MAA) via RAFT polymerization to yield water-soluble, pH-
responsive, amphiphilic, well-defined copolymers. Hemolysis assays revealed that the copolymers with 20
mol% UDAMA content demonstrated pH-dependent hemolytic activity.
13
Production of Biologicals by Genetically Engineered Microorganisms
E. C. Akdur
Hacettepe University, Chem. Eng. Dept. and Bioeng. Div., Beytepe, 06800, Ankara, Turkey
Biologicals – also known as “biological medicinal products” or “biopharmaceuticals” – can be composed
of sugars, proteins or nucleic acids or complex combinations of these substances (such as vaccines or
mAbs), are used for therapeutic or in vivo diagnostic purposes, and by definition (in European Union
regulations), are produced by means other than direct extraction from a native (nonengineered) biological
source. Health and safety concerns, environmental sustainability, enhanced quality criteria and advances
in recombinant DNA technology prompted investigations into production of biologicals using genetically
engineered microorganisms, paving the road to medically valuable products from commercially feasible
processes. While Escherichia coli stands out as the preeminent host for recombinant protein production
in general (50-60% of all commercial proteins), approximately 30% of biopharmaceutical proteins are
produced in E. coli. The difference is mainly due to the effect of glycosylated proteins, where mammalian
cell-lines are currently the preferred host. The crucial glycosylation machinery is not fully present in wild-
type yeast and absent in wild-type E. coli, which results in an immune response or faster renal clearance
when therapeutics from these sources are administered to humans. Thus, ambitious research world-wide
in the last decade has been on humanizing the glycosylation pathways of yeast and more recently of E.
coli. Glyco-engineering tools are also required along the way. Moreover, designing the optimal system for
recombinant glycoprotein production involves many crucial steps. Current status of research in glyco-
engineering tools and bioprocess optimization towards glyco-engineered microorganisms with a specific
emphasis on our collaborative efforts will be presented.
14
Synthesis and Characterization of Self Assembled Nano/Micro Sized Structures Formed by
Catanionic Molecules
E.G. Gok, N. Aydogan*
Hacettepe University, Chemical Engineering Department, Beytepe, 06800, Ankara, Turkey
Nanotubes are extensively used in basic sciences such as chemistry, biology and physics and most
importantly they are also used in biotechnological applications as biosensors, in drug delivery systems,
diagnostic and therapeutic applications. Production methods of nanotubes are very important as well as
their size, shape and surface functionality. Nanotube formation can take long time than expected or can
be expensive in some methods. One of the methods used to obtain self assembled nanotubes is heating
and cooling of amphiphilic molecules in solution but this requires extra energy. Recently it is
demonstrated that nanotubes can be produced with mixtures of anionic and cationic surfactant
molecules. In this study in order to obtain easy, quick and inexpensive self assembled nanotubes, cationic
and anionic (catanionic) molecules which can be found commercially or synthesized easily are mixed at
different experimental conditions such as temperature, pH, concentration etc. CTAB (N-Cetyl-N,N,N-
trimethyl-ammonium bromide), HTAB (hexadecyl trimethyl ammonium bromide) and these molecules’
hydroxyl derivatives are used as cationic molecules and PFOS (Perfluorooctane sulfonate), PBSA (2-
phenyl-5-benzimidazole sulfonic acid), LCA (lithocholic acid) and a unique molecule which is synthesized
in our research group are used as anionic molecules. Characterization of nanotubes are made at different
conditions and times. It’s seen that the length of the nanotubes increase with time compared to their
original form and helical ribbons turn to tubular nanotubes by closing the spaces between them.
Moreover, some examples about how these structures can be used is shown.
15
The Investigation of Inhibition Effect of Bortezomib on Human
DNA Topoisomerase I and II Enzymes
E. Oksuzoglu*, C. Tirinoglu, B. Kerimoglu, K. Ozturk
Aksaray University, Faculty of Science and Art, Biology Department, Aksaray, Turkey
DNA topoisomerases are ubiquitous enzymes that control and modify the topological states of DNA. The
activity of topoisomerases is essential for several cellular processes such as replication, transcription and
chromosome condensation. For this reason, the inhibition of eukaryotic topoisomerases is widely used in
cancer therapy. Bortezomib is a powerful proteosom inhibitor which used in the treatment of
hematological malignancies. In this study, we investigated the inhibitory effect of bortezomib on human
topoisomerase enzymes. The interaction of bortezomib with human type I and type II topoisomerase
enzymes were applied by using cell-free systems. The inhibition effect of bortezomib was determined with
relaxation assay. IC50 values of the bortezomib were calculated using the S probit analysis program.
Bortezomib was found the inhibition effect on human topoisomerase I enzyme at 0.5, 1 and 2 mM
concentrations. At the same time, the inhibitory effect of bortezomib was detected on human
topoisomerase II enzyme at 2 mM concentration. Our results observed that bortezomib inhbits both of
topoisomerase enzyme activities. These results suggested that bortezomib can be increased
chemotherapeutic effect if it used with topoisomerase inhibitor agents.
16
Gold-Nanoparticles for Specific Targeting and Delivery of Oligonucleotides
to Human Breast Cancer Cells
C. C. Aktas*, A. K. Ozden*, A. N. Dizaji**, T. Kutsal**, E. Piskin**
Hacettepe University, Faculty of Medicine, Department of Medical Biochemistry* and Faculty of Engineering,
Bioengineering Department**, Ankara, Turkey
Gold nanoparticles are effective tools to transfect cells for gene therapy. Here, gold particles are
conjugated with transferrin in order to target estrogen receptor specific antisense oligonucleotides. Gold
nanoparticles are activated by thiol groups which enabled the attachment of both a protein and and an
oligonucleotide. Gold particles in cells were visualised by microscopy. Cell protiferation was detected by
MTT and estrogen receptor expression was measured by real-time PCR. Human breast cancer cells
expressing estrogen receptor, MCF 7 have efficiently taken up these conjugates posibly though the uptake
of transferrin receptors. The antisense oligonucleotides againts estrogen receptor were able to suppress
estrogen receptor mRNA expression. Further studies are being carried out using this delivery system
against other overexpressed breast cancer specific genes and their messenger RNA.
17
Bio-Inspired Surfaces for Detection
G. Demirel
Gazi University, Bio-inspired Materials Research Laboratory (BIMREL), Department of Chemistry, Ankara, Turkey
The ability to control the physicochemical properties of surfaces is important for many areas such as
biomedical or optical coatings, sensors, and catalyst supports. We have been developing nanostructured
polymeric and metallic thin films based on oblique angle deposition (OAP) method for these applications
without using any lithography techniques or template materials. These films posses’ novel anisotropic
(directional) properties which could be potentially manipulated based on the growth conditions and the
deposition parameters. The surface‐to‐volume ratio of structured films is very high and the available
surface area increases by more than two orders of magnitude in relation to the bulk film. We are studying
nucleation, crystallinity and growth as well as pore size and geometries of nanostructured thin films. Our
technique opens a new wealth of applications to assemble many possible combinations of monomers or
metallic precursors that have desired functional groups or plasmonic features for creating novel thin films.
In this presentation, we will describe our process for creating nanostructured thin films and present
results concerning their applications.
18
Electrochemical Detection of Bovine Serum Albumin before and befter
N-homocysteinylation at Disposable Sensor Platforms
E. Eksin and A. Erdem*
Ege University, Faculty of Pharmacy, Analytical Chemistry Department, Bornova, 35100, Izmir, TURKEY
Homocysteine-thiolactone (HTL) is known that the product of homocysteine (Hcy) oxidation. The thioester
chemistry of HTL underlies its ability to form isopeptide bonds with protein lysine residues, which may
impair or alter the protein’s function. HTL modification is a unique post-translational protein modification
that is recognized as an emergent biomarker for cardiovascular and neurovascular disease. In the present
study, we developed a reliable, selective and sensitive single-use protein sensor based on pencil graphite
electrode (PGE) in combination with differential pulse voltammetry (DPV) technique. Using bovine serum
albumin (BSA) as a model protein, the effect of N-homocysteinylation onto the protein damage was
studied. The voltammetric detection of BSA before and after N-homocysteinylation in the medium of fetal
bovine serum was performed. The experimental parameters, such as the concentration of BSA, HTL, and
the incubation time of HTL with BSA were optimized. This detection protocol may possibly be developed
furtherly as a practical assay for direct sensitive and selective voltammetric determination of some of
damaged proteins.
19
Design and Development of Novel Large Scale Applications in Micro/Nanophotonics
E. Ozgur 1
1 Bilkent University, Institute of Materials Science and Nanotechnology, Ankara, Turkey
Micro- and nanoscale devices for enhanced light-matter interactions enable observation of many
interesting and unprecedented physical phenomena, among which optical microcavities and
photoconductive nanostructures enjoyed an exponential increase regarding the amount of related
research and publications in the last decade. Optical microcavities with ultra-high light confinement
capability found numerous applications, and probably the most outstanding breakthrough was label-free
biosensing with single molecule sensitivity. Photoconductive nanowires, on the other hand, are
characterized to have improved semiconductor properties compared to their bulk counterparts. While
these achievements are spectacular, new problems immediately emerge, especially regarding large scale
applications of these novel technologies, restricting their extensive use. This talk will describe some novel
approaches towards facile and reliable utilization of optical microcavities and semiconducting nanowires
as biological sensors and photodetectors with wide applicability, by introducing appropriate surface
chemistry in order to achieve high detection selectivity, and a novel nanowire fabrication and assembly
method for macroscale integration of nanostructures, respectively. These results might have important
consequences regarding future progress in the relevant fields.
20
Covalent Immobilization of Heparin on Polyurethane Films
For Anti-adhesive Property
F. Kara1*, E. A. Aksoy2, Z. Yuksekdag3, S. Aksoy1 and N. Hasirci 4,5,6
1Gazi University, Faculty of Sciences, Department of Chemistry, Ankara, Turkey
2Hacettepe University, Faculty of Pharmacy, Department of Basic Pharmaceutical Sciences, Ankara, Turkey 3Gazi University, Faculty of Sciences, Department of Biology, Ankara, Turkey
4METU, BIOMATEN, Center of Excellence in Biomaterials and Tissue Engineering, Ankara, Turkey 5METU, Department of Chemistry, 6Biomedical Engineering Graduate Dept., Ankara, Turkey
Surface properties of polymers have become progressively important in the field of biomaterials. To
control the chemistry, topography and hydrophilicity of material surfaces is likewise a way to influence its
biocompatibility and bacterial affinity. Therefore, surface should have been taken into account when
developing novel anti-infective biomaterials. Heparin (Hep) is a biocompatible polyanion with
anticoagulant activity. High negative charge density of Hep prevents the adhesion of bacteria and
therefore, this biopolymer is a proper candidate to act as anti-adhesive coatings. In this study,
polyurethane (PU) films were synthesized in medical purity from diisocyanates and polypropylene
ethylene glycols without using any other ingredients. Surfaces of PU films were activated by plasma glow-
discharge and modified by covalent immobilization of heparin. The surface wettability was improved after
heparin immobilization. ESCA demonstrated the sulfur peaks and AFM showed the alteration of surface
topographies after Hep immobilization. PU-Hep samples eradicate Gram negative (Pseudomonas
aeruginosa) and Gram positive (Staphylococcus aureus) bacteria completely after 24 h incubation. PU-Hep
films also reduced the number of adhered bacteria effectively. The results demonstrated that, surface
modification with Hep is an effective technique to control the antibacterial and anti-adhesive properties
of biomaterials.
21
Voltammetric Detection of Aptamer in Intraction with Human
Activated Protein C Using Magnetic Beads Assay
G. Congur, A. Erdem*
Ege University, Faculty of Pharmacy, Analytical Chemistry Department, Bornova, 35100, Izmir, TURKEY
Aptamers are nucleic acid ligands, which are isolated from a synthetic nucleic acid pool by Systematic
Evolution of Ligands by EXponential enrichment (SELEX). They can recognize their target molecules; amino
acids, drugs, proteins, etc. There has been many reports which evaluated aptamer based assays by optic,
piezoelectric or electrochemical techniques. Activated protein C (APC) is a serine protease and the key
enzyme of the protein C (PC) pathway. APC has crucial properties for protection of endothelial barrier
function. APC resistance is life-long effected process and disregulation of PC pathway. Recombinant APC
has been used as a therapeutic for sepsis treatment. There are several studies for APC detection by ELISA
and fluorometry. Herein, the interaction between APC and its DNA aptamer (DNA APT) was performed at
the surface of magnetic beads (MB), and then voltammetric detection was performed by using disposable
graphite electrode. APC was firstly immobilized onto the surface of carboxylated MBs, then, the
interaction performed in the presence of amino linked single stranded DNA APT was monitored based on
the changes at the guanine oxidation signal measured by differential pulse voltammetry. This assay
presented the accurate, reliable and fast analysis of APC.
22
Electrochemical Detection of Interaction of Anticancer Drug Lumazine with DNA
Using Carbon Nanotubes Modified Sensors
H. Karadeniz*, E. Eksin, A. Erdem*
Ege University, Faculty of Pharmacy, Analytical Chemistry Department, Bornova, 35100, Izmir, TURKEY.
[email protected] and [email protected]
The reported strategies for the electrochemical monitoring of nucleic acids and biomolecular interactions
based on two different methods; (a) sequence specific hybridization processes based on the oxidation
signals of electroactive DNA bases or (b) the detection of small molecules, which bind with nucleic acid by
intercalation or complexation such as, the metal complexes, antibiotics, pesticides and pollutants. At the
last decade, there has been increasing considerable attention for the usage of carbon nanotubes (CNT)
based transducers, including their applications on the development of electrochemical biosensor systems.
In this study, an electrochemical detection of interaction between anticancer drug Lumazine (LMZ) and
DNA was studied using single walled carbon nanotubes modified pencil graphite electrodes (SWCNT-PGEs)
in comparison to pencil graphite electrodes (PGEs) by by using voltammetric technique under the
optimized experimental conditions. Electrochemical impedance spectroscopy (EIS) was also used to
characterize the successful modification of CNTs onto the surface of PGEs.
23
Animal Models Mimicking Maxillofacial Disorders
I. Vargel MD, PhD
Hacettepe University, Department of Plastic and Reconstructif surgery and
Department of Bioengineering, Ankara, Turkey
The repair of large segmental bone defects due to trauma, inflammation and tumor surgery remains a
major clinical problem. Animal models were developed to test bone repair by tissue engineering
approaches, mimicking real clinical situations. Studies differed with regard to animals (dog, sheep, goat),
treated bone (femur, tibia, mandible,cranium), chemical and structure features of the scaffolds. Still, bone
formation and healing of the segmental defect have advantage which is always observed when scaffolds
are used. Indeed, continuous implementations tests provide new meaning of defects treatment and cure.
However, based on results so far one of obtained animal models and pilot clinical studies can affirm that
the bone tissue engineering approaches, although successful in most cases, need further validation before
a wide application in clinics. Problems encountered in the clinical treatment of maxillofacial bone defect
or surgical techniques that are being used for the development of models which can be used in the studies
were selected. In vivo studies of small animal models are explained with the three selected indications /
benefits will be described. these are; 1- critical size cranial bone defects in rat model. 2- in rat model of
bone distraction. 3- in the rat alveolar defect model.
24
Electrospun Matrices as Tissue Engineering Scaffolds
K.Tuzlakoglu
Yalova University, Department of Polymer Engineering, Yalova, Turkey
In repair or regeneration of the damaged tissues, mimicking the natural ones is the convenient way to
achieve efficient and rapid functional outcomes. Nanofibers play a crucial role in tissue engineering by
serving as matrices for cellular growth, proliferation, differentiation, and new tissue formation in three-
dimensions due to their high surface area to volume ratios and high porosity of the fibers. Electrospinning
is a conventional but new attractive method in biomedical field that can create nanofibers with various
patterns depending on the application. Electrospun nanofibers present a quite similar structure to natural
extracellular matrix which is mainly consisting of fibrous proteins such as collagen, and elastin. This
technique has been used to engineer almost all tissues, for instance skin, bone, sciatic nerve, articular
cartilage, and tendon. However, the difficulties in obtaining 3D matrix with enough thickness are always
encountered as drawback of electrospinning method. To overcome this, different scaffold processing
techniques can be combined with electrospinning. In our studies, we also use electrospinning to develop
bilayer scaffold for skin tissue regeneration. Besides this, in our recent studies we proposed a new design
spiral shape scaffolds consist of aligned nanofiber membranes from two different polymers, namely
polycaprolactone and silk fibroin, for tendon tissue engineering.
25
Study of the Host Ranges of Salmonella SP. Specific Bacteriophages
Kh. Makalatia1,2, N. Karumidze 1,2, I. Kusradze1,2, I. Ediberidze1, D. Lee3, G. Natroshvili1, M.
Goderdzishvili1,2, N. Chanishvili1,2, A. Coffey3, I. Cooper4, J. Caplin4
1Eliava Institute of Bacteriophage, Microbiology and Virology, Tbilisi, Georgia
2Eliava BioPreparations Ltd., Tbilisi, Georgia 3Cork Institute of Technology, Department of Biological Sciences, Bishopstown, Cork, Ireland
4University of Brighton, School of Environment & Technology, Brighton, UK
Salmonella causes a wide spectrum of disease, including gastroenteritis, enteric fever (caused by typhoid
and paratyphoid serotypes), bacteremia, focal infections, to a convalescent lifetime carrier state. The
majority of cases of Salmonella infections are food-borne. Contaminated foods are often of animal origin,
such as beef, poultry, milk, or eggs, but any food, including vegetables, may become contaminated. Thus,
rapid methods of pathogen testing have been gaining increasing interest in the food industry. In recent
years, different strategies to employ phages for detection have been put forward. Assay (PAA) is a
technique based on the phage lytic cycle, which allows detection of bacteria in the sample even if it
remains in the non-cultureable state. Testing of in vitro susceptibility is crucial for selection of proper
phages applicable for detection of pathogens. The present study aims selection of the phages active
against Salmonella sp. which would be then used for early and rapid detection of Salmonella in water and
food samples. Altogether four bacteriophage clones (vB_S.e._B1, vB_S.e._B3, vB_S.tm_BS &
vB_S.tm._MG) active against Salmonella sp. and a traditional commercial phage preparation produced by
the Eliava BioPreparations Ltd. (Tbilisi, Georgia). The phage clones have been isolated from environmental
sources (sewage and sea water samples) in Georgia. 141 Salmonella used for screening were isolated in
Ireland. The strains were isolated from porcine, bovine, poultry, duck, human, vegetable and cheese
sources. Traditional spot test methodology described by Adamas (1958) has been used screening of the
susceptibility of Salmonella strains. The phages have been screened against 141 strains related to
S.typhimurium, S.dublin, S. enteritdis, S.newport , S.derby, S.poona, S. braenderup, S. uganda, S.
senftenberg, S. bredney , S.infantis , S. anatum , S.virchow , S. java , S.kentucky and S. bareilly. Phage
vB_S.e._B1 lysed 92,9% of Salmonella strains, vB_S.e._B3 – 93,6%, vB_S.tm_BS – 92,2%, vB_S.tm._MG –
53,2%. Effectiveness of the traditional commercial preparation Intesti-bacteriophage used for treatment
and prophylaxis of intestinal diseases was 90%. Intesti-bacteriophage is composed of a number of phage
clones with overlapping host ranges strengthening effectiveness of phage preparation. Three out of four
tested phage clones demonstrated higher effectiveness towards Salmonella sp. than the commercial
preparation. The phage clones tested in the scope of the present study demonstrated effectiveness
towards broad host range related to Salmonella sp. and may be recommended for construction of the
Salmonella specific phage-based detection systems.
26
Endogenous Versus Exogenous Approach to Regenerate Intervertebral Disc Damage
M. Alini
AO Research Institute, Musculoskeletal Regeneration Program, Davos Platz, Switzerland
There is evidence that implantation of bone marrow derived mesenchymal stem cells (MSCs) into
damaged tissues may regenerate that organ. MSCs have increasingly been recognized as a promising
source of stem cells for tissue repair and regeneration therapies. Indeed, recent studies have shown that
human MSCs have the capability to survive within the several tissues. Injection of human MSCs into
injured porcine spinal discs, rat disc degeneration models, and bovine caudal discs in vitro demonstrated
MSC survival and differentiation towards a disc-like phenotype. Similarly injections of MSCs within
cartilage injuries and bone fractures have shown healing potential. It is, however, not yet clear whether
MSCs could also release biological factors, which will be able to stimulate the resident cells or activate the
potential progenitor cells present within these tissues. We have now shown that MSCs have the ability to
migrate (homing) towards sites of disc injury and aid wound healing and tissue repair, using our whole
organ culture system. Similarly others have shown similar healing mechanism in cartilage, where
progenitor cells migrated at the defect side upon the presence of a modulating growth factor. These
alternative findings are opening new potential regenerative strategies for the repair of injured tissues,
either by the systemic delivery of MSCs or by activating the resident progenitor cells within damage
tissues. Such approaches will be clinically less invasive and more friendly from a regulatory prospective.
27
Use of Nanoparticles for the Delivery of Genetic Materials in Prevention of Restenosis
N. T. Lacin1, G. G. Utkan2, T. Kutsal3, E. Piskin3
1Yıldız Technical University, Science and Technology Application and Research Center, Istanbul, Turkey
2TUBİTAK MRC, Genetic Eng. and Biotech. Institute, Enzyme and Fermentation Tech. Lab., Kocaeli, Turkey 3Hacettepe University, Chem. Eng. Dept., and Bioeng. Div., Beytepe, Ankara, Turkey.
Coronary balloon angioplasty and coronary stenting have become more & more popular than surgery
because of lower morbidity and mortality rate and reduced hospital stay following the procedure.
However, injury of arteries during angioplasty and stenting causes cell stimulations in tissue. Cell
movement and thrombosis lead to re-narrowing of widened vessel called restenosis. With the aim of
inhibition of restenosis, several new types of carriers and technology have been developed and a great
number of gene therapy methods have been studied using non-viral vectors. Several studies have been
carried out for delivery and controlled release of genes encoding antiproliferative proteins, miRNAs,
peptide structures, siRNAs to the target tissues through different nanoparticles. However, some key
issues, including vector safety and delivery mechanisms, still have to be resolved before percutaneous
gene therapy can be widely applied in clinic. In our previous study, we have used TIMP-2 (antiproliferative
protein) encoding plasmid/PEG-lated monosized nanoparticles (poly (St/PEG-EEM/DMAPM)) complexes
for the transfection of smooth muscle cells. TIMP-2 expression was significantly higher in transfected
smooth muscle cells compared to non-transfected cells.
28
Supramolecular Amphiphilic Glycopeptide Nanosystems and Their Effect on the
Chondrogenic Differentiation
M. Sardan, S. Ustun, E. Arslan, A. B. Tekinay* and M. O. Guler*
Bilkent University, Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center
(UNAM), 06800, Ankara, Turkey
Artificial multivalent carbohydrate systems have great importance due to the potential biological
interactions. Self-assembly mediated by non-covalent interactions such as hydrogen bonding,
electrostatic, hydrophobic, Π-Π, and van der Waals interactions is a effective approach to construct these
multivalent glycoconjugate materials. This energy efficient technique provides stability and solubility in
aqueous solution and displays discrete morphologies. By combined help of the noncovalent interactions,
self-assembling peptide amphiphile molecules can form high-aspect-ratio nanofibers. Side groups on the
peptide skeleton afford multivalency, which provide an interesting platform to explore several receptor-
ligand interactions. In this study, after amphiphilic property is gained by the conjugation of alkyl chain to
the end of the glycopeptide, multivalent glyconano structure emulating glycosaminoglycan functions was
formed by introducing oppositely charged peptide amphiphile to the system. In other words, native
cartilage extracellular matrix was tried to be imitated and it resulted in bioactive signals on the
glycopeptide nanostructures. Therefore, it is mainly focused on the structure of hyaluronic acid which is
abundantly found in cartilage tissue. This glycosaminoglycan mimetic self-assembling nanofibers are used
as a scaffold to conduct in vitro chondrogenic differentiation of mouse mesenchymal stem cells (mMSCs).
29
Importance of Composites in Medical Applications
Nesrin Hasirci
Middle East Technical University, Faculty of Arts and Sciences, Department of Chemistry,
Graduate Depts. Biomedical Engineering, Biotechnology, Polymer Science and Technology, Micro and
Nanotechnology;
BIOMATEN, Center of Excellence in Biomaterials and Tissue Engineering, 06800 Ankara, Turkey
Biological tissues are composed of cells as well as organic molecules, inorganic particles and ions which
come together with a very delicate harmony in an aqueous media having a complex composite structure.
About thirty years ago, hydroxyapatite was used as the bioactive and reinforcing phase in polyethylene to
produce a bone substitute, and then composites gained importance in medical applications. Today, almost
every material, medical device or tissue engineering scaffold, are prepared as composites to match the
desired mechanical strength, bioactivity and biodegradability of the host tissue. Materials can be prepared
as antithrombogenic, antimicrobial, antifungal as well having enhancing functionality for cell proliferation
and angiogenesis. Additives such as bioactive molecules, calcium phosphate or zeolite particles, micro or
nano particles, fibers and tubes controls the properties while the pristine material forms the main matrix.
In general, composites have higher strength where the additives reinforce the polymeric matrix and
impede crack propagation. For tissue engineering applications, scaffolds made of biodegradable polymers
have high bioactivity and high ability to bond to soft and hard connective tissues. Presence of particles
which release some ions as calcium, phosphorous, sodium, zinc or magnesium play a critical role in
providing suitable active media for cell attachment and proliferation in bone tissue engineering. In soft
tissue applications, tendon, muscle or vascular grafts materials having elastomeric properties are needed.
Meanwhile, composite nano or micro particles can be used in the design and production of drug delivery
carriers in order to produce efficient bioactivity, and can be added into the scaffolds or devices to achieve
sustained or sequential delivery of bioactive molecules. The main approach is to create the biological
activity and properties as close as the natural tissues. The talk will give some examples about the
composite systems used in various applications.
30
Tailored Molecules for biomimicry
Nihal Aydogan
Hacettepe University, Chemical Engineering Department, Beytepe, 06800, Ankara, Turkey
Biomimicry can be a powerful concept and a practical tool in the development of new materials. Nature
and technology serve different goals, usually under very different constraints. The extent of the symbiosis
between technology and biology has been investigated quantitatively in literature revealing that the
present technology solves problems largely by manipulating the use of energy, while biology relies heavily
on structure and information storage. It can be instructive, however, to study nature’s materials,
processes and devices, and so identify situations where nature offers useful solutions to properly focused
questions that may or may not have been posed first by technology. This analysis is useful because it helps
us to focus on which aspects of the nature might be most usefully transferred to technology via the
practice of biomimicry. There are several good examples showing the importance of understanding
importance of structure in bio-related processes. For example, natural protein structures are remarkably
precise and can serve as scaffolds upon which new materials can be engineered. By redesigning
architecture and self-assembly behavior at the molecular level, one can customize these biological
complexes to yield novel and non-native functional properties. This knowledge can be also use to design
synthetic molecules which form self-assembled structures with desired functionality. Throughout the
presentation examples of how the molecular tailoring can be utilized to get new materials with desired
functionality are planned to be given. These examples range from the self-assembled structures to
synthetic molecules which mimics the selected function specific lung surfactant proteins.
31
Nanostructured Wound Dressing Materials
A. Akhmetova1, T. Nurgozhin1, I.U. Allan2, M. Illsley2, R. Shevchenko3, S. Mikhalovsky*2, 4
1Nazarbayev University, Center for Life Sciences, Astana, Kazakhstan
2University of Brighton, School of Pharmacy and Biomolecular Sciences, Brighton, UK 3Pharmidex Pharmaceutical Services Ltd, London, UK
4Nazarbayev University, School of Engineering, Astana, Kazakhstan
[email protected]; [email protected]
Macroporous cryogels containing two key components of the dermal extracellular matrix, fibrinogen and
collagen derived gelatin, and their composites with nanoporous activated carbon microbeads, were
evaluated for use as dermal tissue regeneration scaffolds. The infiltration of human dermal fibroblasts
into these matrices was quantitatively assessed in vitro using a combination of cell culture and confocal
laser scanning microscopy. The pore structure of the activated carbon component was assessed using low
temperature nitrogen adsorption and mercury porosimetry. The extent of cellular infiltration, as
measured by the number of cells/distance travelled versus time, was found to be positively correlated
with the fibrinogen concentration of the cryogel scaffolds; a known potentiator of cell migration and
angiogenesis within regenerating tissue. An analysis of the proteins expressed by infiltrating fibroblasts
revealed that the cells that had migrated into the interior portion of the scaffolds expressed
predominantly F-actin along their cytoplasmic stress fibres, whereas those present on the periphery of
the scaffolds expressed predominantly α-smooth muscle actin, indicative of a nonmotile, myofibroblast
phenotype associated with wound contraction. The deposition of cellular fibronectin within the matrices
was closely associated with the location of infiltrating cells and constituted a readily observable ‘front’
that we suggest could act as a useful guide to determine the extent of cellular remodelling of a dermal
regeneration template. In conclusion, the cryogels produced in this study were found to be biocompatible
and, by alteration of the fibrinogen content, could be rendered more amenable to cellular infiltration.
Addition of the activated carbon component increased the efficiency of composite wound dressings in the
treatment of chemical burns. In this application the composite materials showed results superior to the
silver impregnated dressing Acticoat.
32
Expression of Plasmids in Cleavage Stage Mammalian Embryos and Generation of
Transgenic Farm Animals by Transposition
W. A. Kues
Friedrich-Loeffler-Institute, Institute for Farm Animal Genetics, 31535 Neustadt, Germany
The ontogenesis of mammals starts with the cell fusion of oocyte and sperm. Subsequently, the haploid
genomes of both gametes form so-called pronuclei, and cleavage divisions of the embryo are initiated. The
microinjection of linearized DNA constructs into one pronucleus is a standard method for producing
transgenic mice, however this approach did result only in low transgenic efficiencies in larger mammals.
Previously, we established a highly efficient alternative approach for ectopic expression of foreign DNA in
mammalian embryos: the cytoplasmic injection (CPI) of supercoiled plasmids into zygotes [1]. The plasmids
were episomally stable in early embryos and promoter-specificity of plasmid encoded genes was maintained.
The cytoplasmic injection worked equally well for minicircles, conventional plasmids and bacterial artificial
chromosomes, and no indications for integration into the embryo genome were found. In contrast, the
cytoplasmic injection of binary transposons, for example the co-injection of a Sleeping Beauty (SB)
transposon and a SB helper plasmid, encoding the SB transposase, readily resulted in stable integration into
the genome via transposition [2, 3]. Thus the cytoplasmic injection transposon plasmids turned out to be a
robust and highly efficient method for germline transgenesis in mice and in large mammals [2, 4]. The
advantages and perspectives of this active transgenesis will be discussed.
33
Hydroxyapatite Based Bioceramics
Y. M. Sahin1*, F. N. Oktar 2,3, O. Gunduz3,4, M. Yetmez5
1Istanbul Arel Univ., Engineer. & Architecture Faculty, Biomed. Engineer. Dept., Istanbul, Turkey,
2Marmara Univ., Engineer. Faculty, Bioengineer. Dept., Istanbul, Turkey, 3Marmara Univ., Centre of Nanotechnology & Biomaterials Applied and Research, Istanbul, Turkey,
4Marmara Univ., Techn. Faculty, Metallur. & Mater. Engineer. Dept., Istanbul, Turkey, 5Bulent Ecevit Univ., Faculty of Engineering, Mech. Eng. Dept., Zonguldak, Turkey.
Skeletal deficiencies, especially resulting from trauma, tumors, or abnormal developments, are quite
common in clinical practice and are usually treated by surgical intervention and grafting (to restore
mechanical functioning and reconstructing the operational areas). Nowadays the bone-graft market is
estimated as US$ 800 million (worldwide 58% autografts, 34% allografts, 8% synthetic materials). The
need for synthetic bone grafts has been increased. Hydroxyapatite (HA) has been used for hard tissue
healing material because of its chemical and crystallographic similarity to the carbonated apatite of
human teeth and bone. Despite their excellent biocompatibility, the application of HA is limited due to
their poor mechanical properties. These non-loadbearing implants can be reinforced by adding various
oxides in order to improve their mechanical strength. The field of bioceramics investigate mainly the
mechanical properties of bovine derived HA (BHA) composites that are doped with several components
such as bioglass, commercial glass, ZrO2, SiO2, ZnO, SnO, MgO, Y2O3, La2O3, Li2O and TiO2 etc. at different
sintering temperatures (1000-1100-1200-1300°C). Various mechanical tests (i.e. compression, micro-
hardness) and cell culture tests presented promising results for these composites. Lately, in our laboratory
CeO2 nano-oxides have been added to HA and many improvements are obtained [1]. In an ongoing study
of us, natural pumice particles are added and promising results are obtained for these bioceramics as well.
Generally the HA particles for natural bioceramics are obtained from human dentine enamel and bone;
bovine bone and teeth; sheep bone and teeth; chicken bone as well as turkey bone by calcination and
sintering. This production method is an economic, safe, and simple method which leads to bioceramics
that mimics the mineral structure of a human scaffold.
34
Nanoparticles for Transfections
G. G. Utkan*1, N. T. Lacin2, T. Kutsal3
*1TUBİTAK MRC, Genetic Eng. and Biotech. Institute, Enzyme and Fermentation Tech. Lab., Kocaeli, Turkey
2 Yıldız University, Science and Technology Application and Research Center, İstanbul, Turkey 3Hacettepe University, Chem. Eng. Dep., Bioeng. Div., Ankara, Turkey
Direct transfer of genetic material into cells is an important issue of transfection. Major challenge of this
process is the design of effective gene delivery vector, controllably and specifically transport plasmid DNA
into the living cells. Although viral vectors are very effective, they have many safety concerns such as
unpredictable cytotoxicity and immune responses. In this regard, non-viral synthetic materials, organic
(lipid complexes, conjugated polymers, cationic polymers, etc.) and inorganic (magnetic nanoparticles,
quantum dots, carbon nanotubes, gold nanoparticles etc.), have been developed as gene delivery carriers.
Among these vectors, nanoparticles effectively meet some requirements, such as ability to condense DNA
into compact complexes which can be readily taken up by cells, the efficient protection of DNA from
degradation by nucleases, and the release of DNA in functional form. Nanoparticles are solid and spherical
structures in the size range of 100 nm. They have large surface area and tunable properties such as size
and surface functionality. Nanoparticles exploited in gene delivery were categorized into four major
groups: lipid based nanoparticles, polymer based nanoparticles, inorganic nanoparticles and hybrid
nanoparticles. In our previous study, monodieperse polymer based cationic nanoparticles and inorganic
based magnetic nanoparticles were prepared. Their complexes with DNA exhibited pretty high
transfection efficiency and low toxicity. It has been showed that they are potentially promising candidates
for further studies in gene delivery and transfection.
35
Synthesis and Characterization of Heparin Immobilized Poly(2-hydroxyethylmethacrylate)
(PHEMA) Based Cryogels For Albumin Purification
D. Çimen*, N. Bereli, A. Denizli
Hacettepe University, Department of Chemistry, Ankara, Turkey
Affinity chromatography is a well-established method for identification, purification and separation of
biomolecules and based on highly specific molecular recognition. In this method, the molecule possessing
a specific recognition capability is immobilized on a suitable support. The molecule to be isolated is
selectively captured by the complementary ligand immobilized on the matrix. Ligand stability is becoming
an increasingly important consideration. The recent trend, therefore, has been to replace high molecular
mass biological ligands with small molecular-mass pseudospecific ligands. Heparin has the ability to
combine with a large number of proteins. In order to eliminate these complications, numerous
approaches have been tried, including minimal intermittent or regional heparinization, removal of excess
heparin by using sorbents or immobilized heparinase, and immobilization of heparin onto blood
contacting polymeric biomaterials. Heparin and heparin–albumin conjugates have been adsorbed
ionically and covalently to several biomaterial surfaces for improvement of blood compatibility. Heparin
is an important anticoagulant, used clinically to minimize thrombus formation on artificial surfaces.
Heparin is an anionic linear polysaccharide chemically known as glycoaminoglycans. Cryogels are novel
polymeric structures with many advantages including large pores, short diffusion path, low pressure drop
and very short residence time. Synthesis of matrix in cryogel form provides many advantages such as
macropores, low pressure drop, large pores, short diffusion path and very short residence times for both
adsorption and elution. In this study, poly(hydroxyethyl methacrylate) (PHEMA) cryogel was produced by
free radical polymerization. These cryogels were activated with cyanogen bromide (CNBr) at pH: 11.5, and
heparin molecules were then immobilized through covalent bonds. The amount of immobilized heparin
was controlled by changing the initial concentration of CNBr and heparin. The obtained cryogels were
characterized with Fourier transform infrared spectroscopy (FTIR), the swelling test and scanning electron
microscopy (SEM).
36
Radiofrequency (RF) and Medical Applications
B. Nasseri *1, Y. Saygılı2, C. Yılmazer2
1 Hacettepe University, Department of Chemical Engineering, Bioeng. Div., Ankara, Turkey
2Gate Elektronik San. ve Tic.A.Ş ,Ankara,Turkey
Radiofrequency (RF) is a technology that is used in many industrial, military and medical applications. In
the last years, technological developments in medicine and related areas bring an increase in RF usage for
the diagnosis and treatment of many diseases and disorders. Some examples of RF usage in medicine are
magnetic resonance imaging, liver tumor ablation, conductive keratoplaspy, treatment of varicose veins,
sleep apnea and snoring. Cancer is also one of the most important diseases of human being in which some
RF methods have been investigated and developed. In RF cancer therapy, an increase in cancerous cell
temperature is aimed to cause the death of these cells by invasive or non-invasive methods. Tumor
ablation is an invasive method in which cancerous cells are directly exposed to RF energy with a probe
while nanoparticle usage is a non-invasive method that uses cancerous cell- nanoparticle interaction for
selective cell targeting before RF application. As a novel method nanoparticle usage provides an attractive
approach for cancer treatment and needs further research for the treatment of increasing cancer cases.
Accordingly, in this study the effect of nanoparticles on RF hyperthermia is analyzed. Fibroblast and breast
cell cultures are interacted with nanoparticles and exposed to RF energy. The temperature increase in the
cell cultures, apoptosis and necrosis results are observed and they are analyzed as a future cancer therapy
method.
37
Development of Medical Laser and Fiber Optical Systems
A. A. Seymen1,2,4, E. Ozgur1, 3, B. Ortac1, 3
1Bilkent University, UNAM - National Nanotechnology Research Center, Ankara, Turkey 2Erciyes University, Faculty of Medicine, Department of Physiology, Kayseri, Turkey
3Bilkent University, Institute of Materials Science and Nanotechnology, Ankara, Turkey 4Gate Elektronik A.Ş., Bilkent Cyberpark, Ankara, Turkey
The minimally invasive techniques in the medicine are preferred by the clinicians as an alternative to the
invasive techniques because of the advantages of the decrease in risk of infection and complications,
speeding up the recovery and release processes, . One of the most widely used minimally invasive
methods is the use of a catheter. The most important of those methods include the treatment of heart and
vessels by the catheter use. Especially for the vessel surgeries, there is a significant increase in the use of
lasers (1) and when compared to RF ablation, this method was shown as more successful (2). Fiber optic
cables are used in the delivery of highly sensitive laser light in the vessels. Vascular occlusion can be
treated or the vessels that became unfunctional can be cauterized and the diseases such as varicose veins
(3) can be treated even if they are highly progressed. The most important factor affecting the treatment
success is the control of the laser output from the fiber optic cable (4). In Turkey, thousands of catheter
aided laser operations are being performed and this increases the import cost for the lasers and
their consumables. The aim of this study is to get the technical information about the fiber optic cables
which will guide the laser and the laser devices used in those applications. Also, this technical information
was used for the production of an industrial device. The ZEMAX simulations of the fiber were performed
and the optimized fiber ends were produced accordingly. Laser device was developed with own the laser
cooling system and electronic card was also designed. The laser device operates at 980 nm wavelength,
0-32W output power range and in both pulsed and continuous mode.
38
Femtosecond Laser Supported Electrophysiology Measurement System
A. A. Seymen1,2,4, E. Ozgur1, 3, B. Ortac1, 3
1Bilkent University, UNAM - National Nanotechnology Research Center, Ankara, Turkey
2 Erciyes University, Faculty of Medicine, Department of Physiology, Kayseri, Turkey
3Bilkent University, Institute of Materials Science and Nanotechnology, Ankara, Turkey
4Gate Elektronik A.Ş., Bilkent Cyberpark, Ankara, Turkey
Electrical events taking place in cells, which are the smallest unit showing the structural and functional
properties of a living organism, possess significant information about revealing the findings of a number
of diseases. Electrophysiological activity takes place ion exchanges across the cell membrane which
separates the cell from its external environment and those ion exchanges can be examined by using
microelectrode measurement techniques which include challenging physical contact and an irreversible
process for the cell. Besides, recently there is an increase in the use of laser technology in medicine and
biology. Especially, by the development of the very short pulsed lasers (femtosecond), there is an
increased demand on the processing of the biological structures in the micro/nano size ranges. This
benefit of femtosecond laser results in finishing the process before the surface heats and get damaged,
especially for the micro and nano level processing, and it leads to new application opportunities in biology.
In this study, we developed an electrophysiology system, highly significant research technique in
medicine, helping to observe the electrical activity in the cellular level by using a femtosecond laser system
without damaging the whole cell. By using the microscope system which we have designed for the
electrophysiology measurements and which we have integrated with the femtosecond laser system,
micro sized holes were created on the heart muscle culture cells (H9C2) placed into the cell bath without
damaging any other part of the cell and it was observed that the electrical activity of cell might be
observed without making a mechanical contact with the cell.
39
Pre-Studies for Polymeric Coating of Titanium Alloy Materials
M. C. Ates *1, H. Turkoglu Sasmazel 1
1Atilim University, Department of Metallurgical and Materials Engineering, Ankara, Turkey
The interaction between solid surfaces and biological systems are critically important to many areas of
medicine, technology and research. In general, only the surface of an implant is in direct contact with the
host tissue, and thus this portion of the material plays a central role in determining its biocompatibility.
The surface of material can change with time, and is often distinctly different from the bulk properties,
because of oxidation and contamination. Although the surface clearly plays an important role in
implant/cell interactions, the relationships between surfaces of the implant, its reactivity with tissue
constituents, and long-term integrity and clinical efficacy are still poorly understood. Therefore in this
study a new implant material were developed which has the approach the combination of scaffold and
implant materials. The scaffold material was a hybrid of natural biodegradable chitosan, and synthetic
biodegradable polymer, poly(ɛ-caprolactone) (PCL). Two different Ti alloy substrates were used to
prepare new implant material: treating the surface of titanium alloy pieces (20x20x2 mm) with a solution
containing hydrochloric acid (HCl) and, hydrogen peroxide (H2O2). Untreated pieces were only cleaned
with distilled water, alcohol and acetone solution. One untreated sample was used as a control group.
Electrospinning of PCL/Chitosan/PCL layer by layer scaffold was performed on the top of those treated
and untreated Ti-6Al-4V alloy implants with the predetermined conditions [1]. After the preparation of
the new implant (combination of PCL/Chitosan/PCL scaffold and Ti-6Al-4V alloy implant) characterization
studies were carried out. SEM photographs of scaffolds showed that uniform, bead free, micro-nano fibers
were obtained. Contact angle values were measured using sessile drop technique (Theta Lite, KSV
Instruments, Finland). The contact angle value of the final implant material was found to be 88.87 ± 4.78.
In the future, the characterization studies including FIB, AFM and SEM will be done. Additionally the
suitability of developed implant material for tissue engineering applications will be checked with various
cell types.
40
Genetically Modified Yeast
M. İnan1,2 *
1 Akdeniz University, Department of Food Engineering, Antalya, Turkey 2 Akdeniz University, Food Safety and Agricultural Research Center, Antalya, Turkey
Over the last several decades, geneticists have learned how to manipulate DNA to identify, extract, move
and place genes of one organism into a variety of organisms that are different genetically from the source
organism. The development of these techniques has allowed us to better understand how DNA and other
molecules in code their genetic information. This information has lead to the treatment of genetic
diseases by replacing the missing protein, recombinant vaccines, and other importatnt applications.
Microorganism become a producers of non-natural products. First recombinant DNA technology
commercialized product was insulin made in Escherichia coli in 1982. Since then, a range of heterologous
expression systems have been developed to supply the demand for recombinant proteins. The products
that are manufactured in microorganisms are purified and are indistinguishable from equivalent
compounds produced in the conventional manner. Different types of organisms have been used to
express recombinant proteins. Eukaryotic expression systems have been developed. The eukaryotic
system that has been highly characterized is S. cerevisiae. There is a large amount of knowledge that had
been accumulated about its genetics and physiology. Furthermore, yeasts offer the ease of microbial
growth and gene manipulation found in bacteria along with the eukaryotic environment and ability to
perform many eukaryote-specific post-translational modifications, such as proteolytic processing, folding,
disulfide bridge formation, and glycosylation. One of the most used yeast expression system is Pichia
pastoris.
41
Investigation of Cell Behavior on Amino Acid Modified Ti Surfaces
M. Türkaydın1, D. Hür2, L. Uzun3, and B. Garipcan1*
2Anadolu University, Department of Chemistry, Eskişehir, Turkey 3Hacettepe University, Department of Chemistry, Ankara, Turkey
Transplantation is the most common method for treatment of large bone deficiencies. However, because
there is insufficient amount of bone substitutes, bone implants are of paramount importance in the area
of bone tissue engineering. It has been searching for artificial bone substitutes as metals, ceramics and
polymers and these are also implanted in the body. So, biocompatibility is an important factor for a
biomaterial. Titanium and its alloys are most preferable biomaterials due to their biocompatibility,
mechanical properties, resistance to corrosion, and osseointegration. For increasing biocompatibility and
osteogenesis of titanium, its surface can be modified by organic molecules. In our research, titanium
surfaces were modified by newly synthesized amido amino acid self-assembled molecules. It is an easy
and time-saving procedure to modify the surfaces. 3-aminopropyltriethoxysilane (APTES) molecule was
conjugated by different amino acids (histidine, tryptophan, serine, leucine), having different hydropathy
indexes. After modification of the surfaces by the each amino acids, histidine and leucine amino acids
were mixed by changing concentrations (1/4, 1/1, 4/1 v/v) in order to create hydrophilic and hydrophobic
regions on the surface. X-ray photoelectron spectroscopy (XPS) results and contact angle measurements
were done for all of the modified surfaces for characterization studies, Besides morphology and
topography, behavior of cells is mediated by chemical structure of the surfaces. Cells react distinctively to
different surfaces and molecules on the surface dictate their fate. Because of these reasons, it is important
to inspect cell differentiation, viability and proliferation on surfaces by changing
hydrophilicty/hydrophobicity features via this method. Response of different cell types (pre-osteoblasts
and adipose-derived stem cells) on these surfaces is under investigation.
42
Extracellular Matrix Microenvironment Regulates Stem Cell Fate
Y. M. Elçin 1,*
1 Ankara University, Ankara University Faculty of Science, and Ankara University Stem Cell Institute, Tissue Engineering, Biomaterials & Nanobiotechnology Laboratory (ElcinLab), Ankara, Turkey
Success of a regenerative therapy depends on many physiological and technical factors that demand
adaptability to target tissue and a particular ailment. When limited only to the delivery of cultured cells,
regenerative approach lacks the finesse that the natural milieu is accustomed. Tissue engineering
solutions create a mechanically sound alternative that will functionally substitute the natural tissue and
also provide a niche that meets micro-mechanical needs of cells to survive, proliferate and even
differentiate at the site of delivery. For this, the natural mechanisms that govern the stem cell fate must
be assessed in detail. Tensional integrity that is present in the micro-environment is as important as the
bioactive molecules in the niche in deriving the fate of stem cells. In nature, micro-environment dictates
and maintains the differentiative fate of stem cells by, providing stiffness, geometric form, attachment
sites, dynamic architecture which is sustained by enzymatic activity and receptor sites, and mechanical
tension. In addition natural ECM carries biologically active molecules, such as mitogens, morphogens,
growth factors, therapeutic nucleotides. Incorporation of signaling factors into the structure of an artificial
biomatrix, allows these factors to be released in response to cellular activity and in a time-dependent
fashion. Combined with a biologically responsive regenerative biomaterial, cell therapy can achieve stem
cell differentiation in vivo, hence increasing probability of ‘graft success’ in an already-ailing site.
Bioartificial scaffolds must enable timely and relevant delivery of biological factors and stem cell function
in a dynamic fashion; they should supply the cells with biologically compatible micro-environmental cues
necessary for sustainment of ECM, differentiated state and proliferation. Artificially synthesized ECM
candidates should be able to approximate these vastly dynamic functions to be able to attain biologically
relevant results. Biologic scaffold materials derived from natural ECM through decellularization hold an
important potential for providing a physiologically compatible alternative to artificial structures. Effective
methodologies are prompted for different tissue types and pathologies that would allow tissues to
preserve the ECM integrity and biologically relevant cues needed for biological activity. For a regenerative
biomaterial to succeed, it must hold or at least successfully emulate the naturally existing constraints that
shape the niche and dictate the fate of stem cells.
43
Modification and Functionalization of Biodegredable Polymeric Tissue Scaffolds
S. Surucu 1, G. Camporeale 2, O. Ozkan 1, R. Gristina 3, F. Palumbo 2, H. Turkoglu Sasmazel *1, P. Favia 2
1Atilim University, Department of Metallurgical and Materials Engineering, Ankara, Turkey
2Aldo Moro University of Bari, Department of Chemistry, Bari, Italy 3Aldo Moro University of Bari, Department of Biology, Bari, Italy
Electrospinning technique has gained increasing attention over the years for fabrication of fibrous
scaffolds in biomedical applications due to its ease of use and functionalization, and the ability to fabricate
fibers with diameters in micro and/or nanoscale [1]. On the other hand, enhancing of surface functionality
and nanotopography with plasma surface modifications has become a crucial part of the biomedical
applications in order to improve the cell adhesion and/or proliferation of the native scaffolds [2]. The main
target of this study was to obtain plasma surface modified natural/synthetic hybrid 3D PCL/chitosan/PCL
layer by layer tissue scaffolds prepared by the electrospinning technique. The surface modifications were
performed by using dielectric barrier discharge (DBD) plasma method with a planar configuration using
parallel plates separated by a dielectric or using coaxial plates with a dielectric tube between them. The
plasma was applied both in continuous and pulsed mode for different durations (20 s, 45 s, 1 min, 2 mins.
and 3 mins.) at different distances (1 cm and 3 cm) under different gas and chemical mixtures (He, H2O,
C2H4 and RGDC) as plasma environment. The contact angle measurements were utilized for optimization
of the plasma modification parameters. Moreover, surface topography and surface chemistry of pristine
and modified scaffolds were examined with SEM imaging and ATR-FTIR and XPS, respectively. According
to the results obtained, scaffolds modified under He+C2H4+H2O for 2 mins. in a pulsed mode (500 ms on,
1 s off) resulted in better hydrophilicity (64.97°) amongst the other plasma modified samples. Finally, the
effects of surface modificaton on Saos-2 cell line (ICLC) were observed qualitatively by microscopic
techniques.
44
Polymer and Metal Oxide Based Monodisperse-Porous Particles and Their Gold Decoreted Forms: Synthesis & Application
Ali Tuncel 1,2,*
1 Hacettepe University, Chemical Engineering Department, Ankara, Turkey 2 Hacettepe University, Division of Nanotechnology and Nanomedicine, Ankara, Turkey
The synthesis methods and applications of monodisperse-porous microspheres made of acrylic
copolymers or various metal oxides will be discussed. Bifunctional monodisperse-macroporous polymer
microspheres were synthesized in the form of poly(3-chloro-2-hydroxypropyl methacrylate-co-ethylene
dimethacrylate), poly(HPMA-Cl-co-EDMA) copolymer by a “staged shape template polymerization”, in
the size range of 2-7 microns. The reactive chloropropyl functionality allowed the functionalization of
porous microspheres with the various ligands particularly with biological importance via simple and single
stage derivatization protocols. The poly(HPMA-Cl-c-EDMA( microspheres were first reacted with
ethylenediamine to have primary amine functionality in the covalently bound form. Then magnetic Fe3O4
nanoparticles were in-situ generated within the microspheres via complex formation with the primary
amine groups. Hence macroporous monodisperse polymethacrylate beads in the magnetic form were
obtained. Either primary amine carrying monodisperse-porous polymer micropsheres or their magnetic
forms were used as starting material in the synthesis of monodisperse-macroporous metal oxide
microspheres. Hence, monodisperse-macroporous SiO2 or TiO2 tained
both in the plain and magnetic forms. In the last stage, gold nanoparticles were covalently attached onto
the surface of magnetic SiO2 or magnetic TiO2 microspheres. Both the polymer and metal oxide
microspheres were evaluated as stationary phase for DNA isolation from the whole blood by a simple
microextraction device. Gold decorated forms of magnetic porous polymer/metal oxide particles were
evaluted as substrate for the detection of biomolecules by Surface Enhanced Raman Scattering (SERS).
Gold decorated forms of magnetic SiO2 and TiO2 microspheres were evaluated photocatalyst or plasmonic
photocatalyst for the removal of endocrine disrupters from aqueous media. Plain and gold decorated TİO2
microspheres were evaluated as a new type of electron transfer media in the dye sensitized solar cells
(DSSCs).
45
Spion-Based Suspension Array and Nanomakers for Rapid Detection of Toxigenic E. coli Strains
A. Çalış*1, F.Y.Ekinci 2, E. Piskin1
1 Hacettepe University, Chemical Engineering Department and Bioengineering Division, Ankara, Turkey
2 Yeditepe University, Food Engineering & Genetic and Bioengineering Department, İstanbul, Turkey
Shiga toxin-producing Escherichia coli (STEC) infection is one of the most prevalent causes of bloody
diarrhea and hemolytic uremic syndrome associated with consumption of contaminated foods all over
the world. Rapid diagnosis of STEC infection and contamination is essential for effective treatment and
preventing diseases. The objective of this study was to develop novel ‘nanomarkers’ and ‘suspension
arrays’ for pathogenic bacteria, specifically E. coli, and its two health threating strains; O157:H7 and O111:
NM in aqueous media and milk, which was based on detection with polymeric fluorescent
superparamagnetic iron oxide nanoparticles (SPION) carrying specific antibodies (nanosorbents) and using
fluorescent microscopy. A three-step process was applied to prepare the nanosorbents. First, magnetite
nanoparticles were prepared by a co-precipitation of iron salts in the size range of 50-200 nm. While the
average size and size distribution of the magnetic nanoparticles measured by a Zeta Sizer were 78.2 nm
and 0.268, respectively, TEM images revealed that their actual size was about 20 nm. Coating with a
polymer layer carrying COOH functional groups, by microemulsion polymerization increased the average
size to 123.1 nm, but did not changed the size distribution significantly. Anti E. coli antibodies were used
as strand-specific bio-ligands against two different strains of E. coli in the ‘suspension arrays’. Two
different fluorescent dyes (FITC and RB) were incorporated to the different nanoparticles carrying
different antibodies to use them in the same medium to detect different strands in parallel. After
separating both batch and flow-through magnetic separators, fluorescence microscopy was utilized to
detect the labeled nanoparticles that were interacted with the target bacteria. Both nanosorbents were
quite selective both in aqueous media and milk resulting rapid detection of E. coli O157:H7 and O111: NM
strains in the same suspension array test within 30 min at room temperature by using simple magnet and
a fluorescent microscope.
46
Three-Dimensional Tissue/Organ Bio-printing
B. Koc*1, S. B. Ozler1, C. Kucukgul1, F. Hafezi1, M. Altunbek2, G. Kuku2 and M. Culha2
1 Sabancı University, Nanotechnology Research and Application Center and Manufacturing Systems and Industrial
Engineering Program, İstanbul, Turkey 2 Yeditepe University, Department of Genetics and Bioengineering, İstanbul, Turkey
The total loss or functional failure of a tissue or an organ is one of the most devastating, important and
costly problem in human healthcare. There is an overwhelming need for substitutes to replace or repair
tissues or organs because of disease, trauma, or congenital problems. Although there have been a lot of
advancements and success in scaffold based tissue engineering, there are some problems with cell to cell
interaction, the assembly and alignment of extra-cellular matrix (ECM) components and the host response
to scaffolds. In this study, three-dimensional (3D) bio-printing of anatomically correct tissue/organ
constructs for tissue/organ regeneration. First, novel computer-aided algorithms are developed to
digitally copy the targeted tissue for anatomically and structurally correct 3D bioprinting. After the
segmentation with imaging and segmentation software, the captured geometry of the aorta was
converted to computer-aided design models. The captured computer model is then used to develop 3D
bioprinting topology which determines how and where cell aggregates and their support structure will be
printed. Multicellular bioink consisting of human fibroblast, smooth muscle and endothelial cells are used
for vascular bioprinting. To support the bioprinted mechanically-weak live cell aggregates, a novel self-
supporting methodology is developed for direct cell printing. Several example tissue constructs are
bioprinted with self-supporting cell aggregates directly from computer models for fully biological and
scaffold-free tissue engineering. The presentation will also discuss the exciting possibilities of bio-printing:
from drug testing, organ replacements to bionics and also discuss the challenges in organ printing.
Acknowledgments: This research is supported by The Scientific and Technological Research Council of
Turkey (TUBITAK) grant number 112M094 and the Sabanci University Internal Grant
47
Poly(HPMA) and poly(Q4-VP) Based Bilayered Antimicrobial Wound Dressing Materials
C. Demirkan1, K. Tuzlakoğlu2, M.G. Şeker3, İ.A. İşoğlu4, S.Dinçer4
1 Yıldız Technical University, Bioengineering Department, İstanbul, Turkey 2 Yalova University, Department of Polymer Engineering, Yalova, Turkey
3 Gebze Institute of Technology University, Department of Molecular Biology&Genetics, Kocaeli, Turkey 4 Abdullah Gül University, Chemical Engineering Department and Material Science and Nanotechnology
Engineering Department, Kayseri, Turkey
Wounds with high rate skin loss cause serious loss of function at wound site and even deaths. To protect
the wound site and to enhance wound healing mechanism, wound dressing materials with different
characteristics are developed. This study aimed to produce poly(4-VP) and HPMA-based bilayer wound
dressing materials enhancing healing mechanism for the wounds having self-healing problem and high
infection risk. These materials were designed to protect wound from secondary traumas caused bacterial
invasion. Synthesis of quaternary poly(4-VP) (poly(Q4-VP)) which is the antibacterial layer of wound
dressing mateial was carried out in two stages. At first stage, poly(4-vinyl pyridine) polymer was
synthesized from 4-vinyl pyridine monomer by free radical polymerization. Then, poly(Q4-VP) was
obtained by quaternization of poli(4-VP) by an alkylating agent. Polymer synthesis and quaternization step
were confirmed by FT-IR. The macroporous spongy structure, as the bottom layer of wound dressing
material, was prepared by cryogelation of HPMA. The bilayered material was obtained by electrospinning
of antibacterial polymer onto the cryogel sponge. Morphological analysis such as cryogel structure,
porosity, fiber morphology and layer integration were examined by SEM. To enhance wound healing
process, ascorbic acid was loaded to sponge part which will have intimate contact with skin. And, ascorbic
acid release was followed by UV spectrophotometer. Finally, antibacterial properties of the materials
were examined against Staphylococcus aureus. According to the results, bilayered, antibacterial,
temporary wound dressings which can stimulate wound healing and have high swelling capacity were
obtained succesfully.
48
Reversed Palmaris Longus Muscle and Carpal Tunnel Syndrome: Case Presentation and
Literature Review
F. I. Can *1, A.M. Ozturk 1, M.S. Senol 1, E.E. Sener 1
1Gazi University, Orthopaedics and Traumatology, Ankara, Turkey
The Palmaris longus muscle (PL) is a fusiform muscle in the upper extremity and considered one of the most variable muscles in the human body. Numerous variations of the PL have been documented throughout the literature. Usually, the anatomical variations of the PL are not symptomatic. Nevertheless, a reversed palmaris longus (RPL) can cause median nerve and less frequently, ulnar nerve compression. It is usually described in the anatomical literature that the RPL is more often on the left side. However, the literature review shows that most of the cases show a right side RPL. In this study we describe a left side RPL of a 25 years old female patient causing carpal tunnel syndrome and discuss the clinical importance of this situation and review the literature.
49
Hydroxyapatite Bioceramic Production from Natural Calcitic Sources
F.N. Oktar*1,2, Y. M. Sahin3, O. Gunduz4,2, B. Ben-Nissan5
1 Marmara University, Engineering Faculty, Bioengineering Department, Istanbul, Turkey
2 Marmara University, Centre of Nanotechnology & Biomaterials Applied and Research, Istanbul, Turkey
3 Istanbul Arel University, Engineering & Architecture Faculty, Biomedical Engineering Department, Istanbul, Turkey 4 Marmara University, Techn Faculty, Metallurgical & Material Engineering Department, Istanbul, Turkey,
5 The University of Technology, Department of Chemistry and Forensic Sciences, Sydney, Australia
Hydroxyapatite (HA) bioceramics are in use at orthopedic and dental surgeries since decades. They have
excellent properties as a healing material. HA materials are generally produced with chemical methods
from reagent chemicals and /or following the calcination-sintering processes of various bone-teeth
sources by applying heat. Nowadays, it is also very popular to obtain HA from various marine sources such
as cuttle fish, corals (with hydrothermal method), mussel shells, sea urchin and sea snail shells (with
mechanochemical - ultrasonication and chemical methods). Recently, it is of interest to produce HA from
chicken egg shells, ostrich egg shells and land snail shells. First of all those egg shells, sea shells and others
are ball milled and sieved under75µm. This fine powder is analyzed with differential thermal and
gravimetric analysis (DTA/TG) to determine the exact CaCO3 content of the material. Subsequently, the
obtained powder is titrated with H3PO4 either on an ultrasonic cleaner or a hot-plate stirrer to set the
stoichiometric ratio of Ca/P equal to 1.667 for HA and 1.5 for TCP. There is also a hydrothermal way of
treatment, which applies high pressure with delicate equipment to coral and cuttle fish structures, in
order to obtain nano-HA. Apart from this high- pressure method, the HA and TCP production through
mechanochemical methods, with a simple equipment also lead to nano-bioceramic production. On the
other hand, especially egg-shells are disposed and not used. Recycling them is a green chemistry and can
save on raw materials. Additionally, Turkish coasts are full with dead sea shells which can be used in
production of low-cost biomaterials with mechanochemical - ultrasonication and chemical methods.
These proposed biomaterial production methods are easy, economic and cost efficient.
50
Lysine-Promoted Colorimetric Response of Gold Nanoparticles: A Simple Assay for Ultrasensitive Mercury(II) Detection
G. Sener1,2 , L. Uzun1, A. Denizli1
1Hacettepe University, Faculty of Science, Department of Chemistry, Ankara, Turkey
2Hacettepe University, Institute of Science, Nanotechnology and Nanomedicine Division, Ankara, Turkey
Contamination of water by heavy metal ions (e.g. mercury, silver and lead) can cause serious environment
and health problems because of their acute and/or chronic toxicity to the biological organisms. For
instance mercury, which is widely released to the environment by industrial activities (e.g. gold mining
and combustion of fossil fuels and wastes) shows great toxicity on mainly renal and nervous systems
through disrupting the activity of enzymes. The most common and stable form of the mercury in water is
its solvated divalent mercuric ion (Hg2+). Therefore, monitoring of Hg2+ levels in water is very important in
terms of waste management, environmental analyzing, toxicology, water safety and water quality.
Although numerous methods have been reported for the analysis of toxic mercury (Hg2+) ions in drinking
water, development of simple, rapid, inexpensive and sensitive sensors still remains a great challenge.
In this research, we develop a simple, yet very sensitive colorimetric assay for rapid detection of Hg2+ from
water. The colorimetric assay is based on the aggregation of the as-prepared citrate capped gold
nanoparticles (AuNPs) in the presence of Hg2+ ions and the positively charged amino acid, lysine. In the
first step, Hg2+ spontaneously reduced on the AuNP surface and formed Hg/Au nanoparticles. Then, lysine
addition to this solution induced aggregation of Hg/Au nanoparticles and resulted in a rapid color change
from red to purple or gray. Detection limit of this inexpensive colorimetric assay is 2.9 nM, which is below
the limit value (10 nM) defined by the U.S. Environmental Protection Agency in drinkable water. Also, the
colorimetric response of citrate capped AuNPs in the presence of lysine is very selective to the Hg2+. In
addition, the colorimetric assay is very fast and all analysis can be completed within a minute.
51
Effect of Boron on Osteogenic Differantiation of Rat Mesenchymal Stem Cells Derived from Bone Marrow and Adipose Tissue
I. Shikhaliyeva 1, E. O. Tuncay 1, M. Gümüşderelioğlu 1,2,*
1 Hacettepe University, Bioengineering Division, Ankara, Turkey 2 Hacettepe University, Chemical Engineering Department, Ankara, Turkey
Boron (B) is a notable trace element in humans which has stimulating potential on osteogenesis. However,
exact mechanism of the effect of boron on bone health is still unknown. So far, the effect of B on the
osteogenic differentiation of the cells have been reported on human bone marrow stem cells, human
tooth germ stem cells and MC3T3-E1 preosteoblastic cell line. The aim of this study was to investigate the
effects of B on the osteogenic differentiation of bone marrow stem cells (BMSCs) and adipose derived
stem cells (AdMSC) comparatively. AdMSCs were isolated enzymatically from the rat adipose tissue and
BMSCs were harvested from the femurs and tibias of the two months old rats for cell culture studies.
Characterization of the cells were carried out with flow cytometry at passage 3-5 to analyze mesenchymal
stem cell (MSC)-specific antibodies and with Oil Red O staining to show if there are any adipocytes in the
primary culture of the cells. Osteogenic and chondrogenic differentiation capacity of the cells were
determined alkaline phosphatase/Von kossa and Safranin O staining, respectively. Boric acid was
prepared as a stock solution to obtain following B concentrations i.e. 1, 10, 100, 1000, 10000 and 20000
ng/mL. Cell culture studies were maintained for 28 days. MSCs viability and proliferation were analyzed
by Presto Blue. The calcium deposition of the cells were determined by Alizarin Red S staining. Real-time
PCR was used to detect the expression of several osteogenic differentiation-related marker genes such as
collagen type I (COL-I), alkaline phosphatase (ALP), osteocalcin (OCN), and bone morphogenetic proteins
7 (BMP-7). The results indicated that increased proliferation and osteogenic differantiation of the MSCs
were achieved by depending upon the B concentrations and cell source. Further studies will be done to
evaluate these results for scaffold-based cell cultures.
This study was financially supported by Turkish Scientific and Research Council with project No:112M705.
52
Biobased Materials for Agrochemical Use
K. Kesenci 1,*
1 Safa Tarim A.S. Konya, Turkey
Good agriculture aims to optimize the use of natural resources, while protecting the long-term, economic
viability of farming activities. Farmers aim for sustainable production of healthier, stronger crops that are
resistant to disease and contribute to supplying abundant, high quality food. Modern crop protection
technologies, in conjunction with developing advanced plant varieties, play an increasingly important role
in achieving this aim. In the agro chemicals market, there is an increasing trend towards the use of bio-
based and non-toxic solvents, because of increasing concern for environmental and safety issues.
53
Chondrogenic Potential of Alginate Microcapsulated Primary Chondrocytes within and Outside of Hydrogels
R. Akçapınar1, C. Çakır Çoban2, M. Türk3 and S. Karahan1*
1 Kırıkkale University, Faculity of Veterinary, Department of Histology and Embriyology, Kırıkkale, Turkey
2 Kırıkkale University, Faculity of Science and Art, Department of Biology, Kırıkkale, Turkey 3 Kırıkkale University, Faculity of Engineering, Department of Bioengineering, Kırıkkale, Turkey
Cartilage tissue has a limited capacity of repair. Mainly for this reason, chondrocyte implantation via
carrier matrices to damaged cartilage areas is among the most current approaches in degenerative joint
disease such as osteoarthritis. Chondrocytic condition as well as biocompatibility and biodegradation of
the carrier matrices are still of scientific interest to a high degree. Chondrocytes, which normally have a
limited mitogenic capacity, gain capacity of proliferation and synthesize collagen type I instead of collagen
type II in 2 dimensional cell culture environment (dedifferentiation). Dedifferentiated chondrocytes are
loaded to 3 dimensional matrices in order for them to regain chondrogenic capacity before implantation
to damaged cartilage regions. However, absence of a mechanism that fully fosters and protects
chondrogenic potential is the main reason behind this ongoing interest. Microcapsulation of chondrocytes
with a semi permeable membrane has been studied for the last few years and opened doors for new
technology opportunities in cartilage tissue engineering. In this proposed study, primary bovine
chondrocytes were microcapsulated with alginate. Bovine chondrocytes, isolated from fetal cartilage
provided from a local slaughterhouse, were expanded in cell culture. Chondrocytes either
microcapsulated or uncapsulated will be cultured for at least 40 days. The chondrogenic capacity were
revealed in sampled chondrocyted at the 5, 8, 15, 30, and 40. days of the culture using histological,
histochemical, immunohistochemical techniques. For this purpose, apoptosis/necrosis test, WST-1 and
MTT cytotoxicity test, toluidine blue staining for GAG deposition were done. All samples will be studies
in triplicate and results will be evaluated statistically. As a consequence, viability of encapsulated
chondrocytes were continued at high level until 40 days. According to results of double staining for
apoptosis and necrosis, apoptosis/necrosis ratio of encapsulated chondrocytes in 5th day were calculated
as %3,03/ %0,61, in 8th day %5,45/ %1,82, in 15th day %5,65/ %3,23, in 30th days %16,39/ % 14,75 , and
40th days %17,31/ %16,54 . further more , according to MTT cytotoxicity test, viability ratio of capsulated
chondrocytes were recorded as 91,37% in 5th day, 84,32% in 8th days, 81,17% in 15th day, 77,65% in 30th
day and 61,30% in 40th day. According to WST-1 test , viability ratio of capsulated chondrocytes were
recorded as 90,72% in 5th day, 84,32% in 8th day, 72,61% in 15th day, 68,35% in 30th day and 62,34% in 40th
day. In toluidine blue staining for detecting deposition of GAG, synthesis were observed after 15 th day.
Immunohistochemical studies for show the collagen type I and type II and RT-PCR will be evaluated for
next studies.
54
Sustainable Biofuels, Biobased Chemicals and Plastics: A Global Challenge or Dream
S. Miertus 1,2*
1 International Centre for Applied Research and Sustainable Technologies (ICARST),Bratislava, Slovakia/Trieste, Italy
2 University of SS. Cyril & Methodius, Faculty of Natural Sciences, Trnava, Slovakia
[email protected], [email protected]
The paper focuses on the survey of potential of renewable feedstock, especially biomass. Biomass is becoming
one of the important forms of renewable energy with a specific emphasis on the development of next
generation biofuels as of the only sustainable solution for the future biofuel industry. The opportunities and
risks of exploiting renewable bio-feedstock for biofuels production and biobased chemical and polymers are
addressed from the point of view of sustainability of products and of related production processes with the
focus on global context. Particular attention is paid to the integrated approach of biorefinery which links the
agriculture and production of biofuels and chemicals/materials and it is becoming a key factor for the viability
of the emerging bio-based industry. Specific attention is given to an overview of the recent progress in science
and technology in the field of next generation biofuels and bio-based chemicals from waste biomass. Capacity
building in the S&T sector is a critical factor worldwide on their way to the sustainable bio-based economy. The
proper planning and analysis of scenarios for specific countries/regions’ (LCA and socio-economic analysis
together with the right choice of resources and conversion technologies) should be the driving force in taking
decisions on biobased production strategies. Along with the production of advanced biofuels, the production
of biobased polymers and plastics and biobased speciality chemicals is being rapidly developed. Biobased
plastics became one of important solutions for environmentally degradable plastics affecting the environmental
sustainability especially for packaging and disposable plastics. We have developed and implemented in last
decade a global program on advanced biofuels and biobased chemicals, and plastics (formerly within the
International Centre for Science and High Technology of the United Nations Industrial Development
Organization (ICS-UNIDO) and recently under new centre International Centre for Applied Research and
Sustainable Technologies (ICARST). Series of projects in the field of advanced technologies for exploitation of
renewable bio-resources for production of biofuels, chemicals and plastics have been developed and some
examples of these projects will be presented.
55
Targeted X-ray Imaging of Breast Cancer Using Bombesin-Gold Nanoparticles Conjugate As a Contrast Agent In Mouse Model
M.Salouti 1,*
1 Islamic Azad University, Biology Research Center, Zanjan Branch, Iran
The frequent overexpression of the gasterin releasing peptide receptors (GRP) in breast cancer cells opens
the door for breast targeting using the bombesin analogs. The bombesin analog, with binding ability to all
GRP receptor subtypes, was activated by nanothink acid as a linker and bound covalently with synthesized
gold nanorods. To increase stability and biocompatibility, the conjugate was PEGyleted. The interactions
were confirmed by UV-vis and FT-IR spectroscopy. The stability assessment proved high optical stability
of GNR-PEG-BBN in human blood serum up to 12 h. The cell binding and internalization studies showed
high specificity and internalization of GNR-Bombesin-PEG towards breast cancer cells (T47D cell line over
expressing GRP receptor). The biodistribution study revealed the accumulation of new nanodrug in breast
tumor in mouse model. The X-ray imaging showed the visualization of breast tumor in mouse model.
56
The Influence of Inflammatory Cells on the In vivo Tissue Vascularization
S. Ghanaati 1,2*
1 Medical Center of the Goethe University, Department for Oral, Cranio-Maxillofacial and Facial Plastic Surgery,
Frankfurt am Main, Germany 2 University Medical Center of the Johannes Gutenberg University, Institute of Pathology, Mainz, Germany
The present overview focusses on the influence of pysico-chemical characteristics of materials such as
size, shape and porosity, on the induction of the material-specific cell and tissue response. Various
synthetic, xeno- and allogenic bone substitute materials and bio-membranes with or without pre-
cultivation with human osteoblasts were implanted into the subcutaneous tissue of small animals, muscle
tissue in goats or the human sinus cavity. The pattern of the inflammatory response to these materials,
i.e. mononuclear vs. multinucleated giant cell generation was systematically evaluated by applying
standardized histological and novel histomorphometrical techniques. The results showed that changes in
size, shape, porosity and chemical composition led to either a mononuclear cellular or a multinucleated
giant cell-based tissue response, which influenced biomaterial vascularization and integration.
Interestingly, the in vivo survival of pre-cultivated osteoblasts on bio-membranes and their propensity for
bone matrix production seemed to be independent of the extent of implantation bed vascularization. The
present data underline the fact that changes in biomaterial physico-chemical characteristics can be used
to guide synthetic materials to induce comparable cell and tissue reaction observed for biological-derived,
i.e. xenogeneic materials. These results encourage the continuation of developing synthetic bone
substitutes and membranes.
57
Enterococcus Phages: Study of Their Potential for Construction of Phage-Based Detection Systems
S. Rigvava1,2, N. Karumidze1,2, K. Makalatia1,2, M. Goderdzishvili 1,2, N. Chanishvili1,*, I. Cooper3, J. Caplin3
1 Eliava BioPreparations, Tbilisi, Georgia
2Eliava Institute of Bacteriophage, Microbiology & Virology, Tbilisi, Georgia 3 University of Brighton, Brighton, UK
Enteroococcus sp are natural inhabitants of the gastrointestinal tracts of humans and other warm-blooded animals. They are also fecal indicator bacteria that along with fecal coli-forms are used to measure the sanitary quality of water for recreational, industrial, agricultural and water supply purposes. Due to their high specificity to pathogens the bacteriophages were recognized as biosensors applicable for detection of water- and food-pollutant bacteria. The study aims to identify the phages with broad host spectrum for their further applications for construction of the phage-based test systems able to detect presence of Enterococcus sp. in environmental samples. 334 strains related to various Enterococcus sp. from different environments in the UK and Sweden in 1998, 1999, 2000 and 2012 were included into the screening. Most of these strains revealed resistance to vancomicin and erythromycin. The strains were screened against five clones of phages: vB_EfS_2, vB_EfM_2, vB_EfM_3, vB_EfS_4, and vB_EfS_Bioni, previously isolated from sewage waters in Georgia using E. faeclais and E. fecium as host the strains. The phage clones vB_EfS_2, vB_EfS_2 and vB_EfS_Bioni belong to the virus group I, order Caudovirales, family Syphoviridea, while vB_EfM_2, vB_EfM_3 belong to the virus group I, order Caudovirales, family Myoviridae. Two clones of phages: vB_EfS_2 and vB_EfS_4 were sequenced, and analysis revealed that the phage vB_EfS_2 is temperate, while vB_EfS_4 is a virulent one. Three other phages were studied for their biological properties, such as host ranges, single growth cycle, etc. According to these results it is possible to conclude that they can be considered as virulent phages as well. To evaluate potential efficiency of the phages for detection of pathogens in different environmental samples, 334 bacterial strains included into the screening were grouped according to their origin: human origin (clinical and hospital water strains, total 126), animal origin (pig, cattle and hen feces, manure and feed, total 99), farm origin (animals 99 & environment including raw and treated wastewaters and soil 88), water origin (raw and treated wastewaters - 88 & hospital waters - 22 & river and sea waters – 21, total 131 strains). The best results in all groups were shown by the phages vB_EfS_4 and vB_EfS_Bioni, where the highest effectiveness of these phages were demonstrated in the group of strains originating from humans and animals. Phage vB_EfS_4 lysed 63,5% of the human and 57,6% of animal strains. Effectiveness of phage vB_EfS_Bioni attained 70,6% on human and 71,7% on animal strains. Effectiveness of these phages on farm isolates was 49,7% and 57,75%; on the strains isolated from waters 48% and 47,3%, correspondingly. Average effectiveness of the phages on the whole set of the screened strains for phages vB_EfS_4 and vB_EfS_Bioni varied between 49% and 55%. The results demonstrated that well-characterized phages: vB_EfS_4 and vB_EfS_Bioni, previously selected for human phage therapy may suit a broader biotechnological application. These bacteriophages demonstrated 49-55% of effectiveness towards different environmental samples of Enterococcus, which may be easily increased up to 90-99% after several rounds of adaptation. Therefore, the bacteriophages vB_EfS_4 and vB_EfS_Bioni can be recommended for construction of phage-based detection systems.
58
Self-Assembled Peptide Nanostructures for Functional Materials
M. Şardan and M. O. Guler 1
1 Bilkent University, Institute of Materials Science and Nanotechnology, National Nanotechnology Research
Center (UNAM), Ankara, Turkey
In this talk, concepts of making materials, which mimic the structure and function of the biological
materials through programmed self-assembly of small molecules and their applications in functional
materials. The self-assembly mechanism that forms the supramolecular aggregates involves non-covalent
interactions such as hydrogen bonds, electrostatic and hydrophobic interactions. Diverse functional
groups were incorporated into nanostructures for functional materials applications. Understanding
interactions in assembly mechanisms of biological molecules has become a crucial factor in the design of
nanoscale materials. For example, protein structure is defined by information encoded in the individual
amino acids. The amino acids are joined together to form peptides, which then fold into complex
structures. A considerable number of the structural features in proteins consist of α-helix and β-sheet
secondary structural components of peptides. Synthetic methodologies provide routes for synthesis of
peptide sequences that are useful in the formation of one-dimensional nanostructures. Non-peptidic
moieties can incorporate novel functionalities into supramolecular systems such as photoswitching units
and ligands for recognition events.
59
Bacteriophage - Our Friends: Their Selection and Practical Application in Different Fields of Science
N. Chanishvili, 1,2* , M. Goderdzishvili 1,2
1 Eliava BioPreparations, Tbilisi, Georgia
2Eliava Institute of Bacteriophage, Microbiology & Virology, Tbilisi, Georgia
Bacteriophages (shortly phages) - bacterial viruses were discovered in 1915 by English bacteriologist
Frederick Twort. Soon after that in 1917 French-Canadian scientist Felix D’Herelle suggested to use
bacteriophages for treatment of animals and humans. Georgian scientist George Eliava was fascinated by
this idea. Together they built up the strategies and developed the methods for isolation and selection of
bacteriophages applicable for different practical purposes. Thus, the phages aimed for therapeutic or
prophylactic applications are recommended to be isolated from the sewage collectors, rivers, lakes and
ponds. Study of biological properties is the main criteria for proper selection of bacteriophages. For
therapeutic and prophylactic phages this is essential to prove their virulent nature, which is based on their
plaque and virion morphology, broad host range, serological and genetic characteristics, etc. Special
requirement are drawn out for diagnostic and/or marker phages (e.g. narrow host range, survival of
bacteriophages in the certain environmental conditions such as pH, UV irradiation, etc.) used for
environmental modeling. The phages aimed to be used for veterinary purposes should be isolated from
the farm environment and be adapted towards the farm isolates. In this case the phages may be used for
therapy or prophylaxis, diagnostic or sanitary purposes for reduction of the number of pathogenic bacteria
or their complete eradication. Phage preparations may be used for prophylactic treatment of plants as
well. Bacteriophage mixtures (“cocktails”) have been traditionally used for therapy and prophylaxis of
bacterial infections in Georgia. The phages nowadays are seen as a possible therapy against multi-drug-
resistant strains of many bacteria. The presentation will focus on such important issues as the safety of
the phage preparations, quality of control methods, etc. Examples of practical application of phages will
be discussed as well.
60
Screening of Newly Isolated E.Coli Phages Against The Strains Isolated from Different Environments
N. Ghudumidze1, K. Makalatia 1,2, N. Karumidze1,2, G. Natroshvili 1, M. Goderdzishvili1,2, M.
Merabishvili1,3, I. Cooper4, J. Caplin4, N. Chanishvili1
1 Eliava Institute of Bacteriophage, Microbiology and Virology, Tbilisi, Georgia
2 Eliava BioPreparations Ltd., Tbilisi, Georgia 3 Ghent University, Ghent, Belgium
4 University of Brighton, Brighton, UK
E.coli presents one of the most common bacterial species of human and animal intestinal microflora.
However several serotypes of E. coli (e.g. enterohaemorrhagic E.coli –EHEC) are notorious for their
pathogenicity. The majority of cases of E.coli infections are food-borne. Contaminated foods are often of
animal origin, such as beef, poultry, milk, or eggs, but any food, including vegetables, may become
contaminated too. Some E.coli bacteria have become resistant to antibiotics, largely as a result of the use
of antibiotics to promote the growth of food animals. Its increasing antimicrobial resistance, prevalence,
virulence, and adaptability are a challenge worldwide. The phages nowadays are seen as a possible
therapy against multi-drug-resistant strains of many bacteria. They may be used also as a prophylactic
mean in animal farms. The present study aims isolation and selection of the phages active against E.coli
for construction of therapeutic or prophylactic bacteriophage mixtures applicable for humans and/or
animals. Commercial phage preparations: Pyo-, Intesti-, Ses- and Enco- bacteriophages along with 4
phage clones from the Eliava phage collection: vB_Ec_4S, vB_Ec_4t, vB_Ec_3M and vB_Ec_PIC were
selected for screening. In additional 5 bacteriophage clones have been isolated from sewage samples:
vB_Ec_6.1, vB_Ec_6.2, vB_Ec_8-1, vB_Ec_8.2 and vB_Ec_10-2. The strains selected for screening included
urology clinical (41), farm (30) and environmental (121) strains. Phage isolation, host ranges, serological
relatedness, resistance to environmental factors were studied by traditional methodology (Adams,
1958). Phage morphology was studied according to Tikhonenko (1969). All five newly isolated phages
belong to order Caudovireales, phages vB_Ec_6.1 and vB_Ec_10-2 are representatives of family
Myoviridae, while vB_Ec_6.2 and vB_Ec_8-1 and vB_Ec_8.2 of family Siphoviridae, species Jersey.
Effectiveness of the newly isolated E.coli phages was compared to commercial phage mixtures and
separate phage clones available from the Eliava collection. Activity of the commercial bacteriophage
mixtures towards clinical strains varied between 56%-90%, while separate phage clones showed activities
varying from 8% to 90%. Among the new phages the best results were demonstrated by phage vB_Ec_10-
2 which lysed 31,6% of cultures. All groups of phages showed low effectiveness (10-15%) against
environmental and farm strains. After the adaptation of the phages to farm strains their activity increased
up to 25% and 41.6% for vB_Ec_8-1 and vB_Ec_6-1, respectively. The phage clones characterized in the
scope of the present study showed high specificity towards clinical strains. Due to adaptation their host
range was extended from 15% to 41%on the farm strains as well. Further adaptation is possible which will
make these phages applicable for construction of therapeutic and prophylactic phage preparations both
for human and animal uses.
61
Optimization of an Experimental Protocol to Reduce Gene Expression Variability in S. epidermidis Biofilms
C. Sousa 1 and N. Cerca* 1
1 University of Minho, CEB - Centre of Biological Engineering, Campus de Gualtar, Braga, Portugal.
S. epidermidis is the most frequently bacteria isolated from human epithelia. Currently, this bacterium
persist as a major cause of hospital and community-acquired infections and it is primarily associated with
infections of indwelling medical devices, by the formation of a structure called a biofilm. Biofilms can
quickly adapt to new conditions and consequently, can result in the appearance of infections that are
resistance to many antibiotics and mechanisms of the host immune defense. The understanding of how
bacteria quickly adapt to the new environment is crucial to devise better therapeutic solutions. Gene
expression studies have been important in addressing these issues. However, a high variability of gene
expression studies can often compromise the results and leads to a higher number of experimental
repeats, with an increase in costs. In this work, we quantified the origin of gene expression variability, by
isolating the individual steps included in the experimental set-up, namely biofilm growth, RNA extraction,
reverse-transcriptase reaction and qPCR. Our results showed that biological sample was the key step
introducing high variability. We devised a simple approach wherein we pooled 20 biofilms in each RNA
extraction. This simply solution was able to reduce gene expression variability 2-3 fold. This was then
confirmed in 3 independent clinical and commensal strains.
62
Dielectric Barrier Discharge (DBD) and Nozzle Type Plasma Modifications of Polymer Based Biomaterials
O. Ozkan *1, H. Turkoglu Sasmazel 1
1 Atilim University, Department of Metallurgical and Materials Engineering, Ankara, Turkey
Hybrid structures composed of natural and synthetic polymers are widely utilized in tissue engineering
applications since the advantages of both are combined without the disadvantages of neither [1].
However, even though these hybrid structures support the cell adhesion and/or proliferation at a certain
level, research towards the improvement of surface functionality and nanotopography is essential.
Therefore, this study focused on the improvement of the surface functionality and nanotopography of the
layer by layer electrospun 3D poly-ε-caprolactone/chitosan/poly-ε-caprolactone hybrid tissue scaffolds by
means of atmospheric pressure plasma method. Two different atmospheric pressure plasma systems
(nozzle type and dielectric barrier discharge (DBD) type) were used for formation/creation of the
functional hydroxyl and amine groups and topographical changes on the surfaces of scaffolds and the
modifications were carried out under different gas medium (air, Ar+O2, Ar+N2). The changes in surface
hydrophilicity were monitored by using contact angle measurements in order to optimize the modification
time and distance for the nozzle type plasma system and the modification time and the gas flow rate for
DBD type plasma system. Additionally, the topographical and chemical characterizations of these
modified surfaces were carried out with SEM and ESCA, respectively. Both nozzle type plasma and DBD
plasma were found to cause nanotopographical and functionality changes on the surfaces of the layer by
layer electrospun tissue scaffolds, however, the shelf life study results indicated that the hydrophilicity
introduced to the surfaces was mainly because of the functionality changes. In conclusion, the samples
treated with nozzle type air plasma for 9 minutes from a distance of 17 cm and the samples treated with
Ar+O2 DBD plasma for 1 minute under 70 cm3/min O2 flow rate were found to have the highest
hydrophilicity compared to the untreated samples. In the future, the topographical changes in individual
fibers and cell-interaction performance of the material will be investigated with AFM imaging and skin
fibroblast cell line, respectively.
63
Bone Surface Mimicked Scaffolds for Ostegeogenic Stem Cell Differentiation
Ö. Demir1, D. Uçkan2, E. Kılıç2, D. Uçkan-Çetinkaya2, B. Garipcan1*
1Bogazici University, Institute of Biomedical Engineering, Istanbul, Turkey
2Hacettepe University, Stem Cell Research and Application Center, Ankara, Turkey
Bone tissue engineering is used for finding new therapeutic methods and accelerated healing in the
treatment of bone defects due to the tumors, traumas and serious inflammation and is developing day by
day. The importance and advantages of bone tissue engineering products are increasing because of the
disadvantages of autografts, allografts and zenografts such as finding suitable donors, rejection of tissue
by immune system or pathogen carrying properties which are commonly using for the treatment of bone
defects. Metals and their alloys, ceramics, natural polymers such as chitin and collagen, biodegradable
and bioabsorable synthetic polymers (poly(l-lactic acid, polycaprolactone) are being used as scaffolds
and/or surfaces in bone tissue engineering. Changing the surface properties of scaffolds may influence
and effect the cell-surface, cell-scaffold interface characteristics and cellular behavior and mechanism of
osteoblasts, stem cells and as well as other cell types. In this study bovine femur bone surface was
mimicked by using polymethylsiloxane (PDMS) elastomer and used as a mold. A biodegrable polymer,
poly (L-Lactic acid) was poured (10% (w/v) in chloroform and 24 h casting time) on the PDMS mold to
obtain bone surface mimicked biodegradable PLA scaffolds. Bone surface mimicked PLA scaffolds were
characterized by Scanning Electron Microscope (SEM), contact angle measurements and Atomic Force
Microscope (AFM). In ongoing studies, the effect of bone surface mimicked PLA scaffolds on the controlled
and directed differentiation of bone marrow and adipose derived mesenchymal stem cells and bone tissue
formation in in-vitro conditions will be investigated.
64
Preparation of Silver Loaded Zeolite NaA from Wheat Husk Silica as An Antibacterial Agent
S. Yucel1*, P. Terzioglu 2, A. Attar1, S. Gurlek1
1Yildiz Technical University, Faculty of Chemical and Metallurgical Eng., Dept. of Bioengineering, İstanbul, Turkey
2Muğla Sıtkı Koçman University, Faculty of Sciences, Department of Chemistry, Muğla, Turkey
The zeolites showing antibacterial properties can be prepared by exchanging the extra framework cations
(Ca2+, K+, Mg2+, and Na+) by suitable metals such as bismuth, cadmium, chromium, cobalt, copper, lead,
mercury, nickel, silver, tin, and zinc. However, silver is the most preferred metal among others due to its
low toxicity and strong activity. On the other hand, the silver loaded supports seem to be a good cost
effective alternative than the use of bare silver as an antibacterial agent. The silver loaded zeolites can be
used in a wide range of application in biomedicine, dentistry and medical textiles for the production of
artificial leathers, diapers, wound dressing materials, tissue conditioners, and shoe lining materials. The
aim of this study was to report antibacterial activity of the wheat husk silica based and commercial zeolite
NaA after ion exchanged with Ag+ against Escherichia coli after 24 h of exposure to 40 mg of the zeolite in
10 mL of nutrient agar. The characterization of zeolites was performed by Fourier transformed infrared
spectroscopy, scanning electron microscopy and X-ray diffraction. As a result, SEM-EDS analysis result
approved that modification of zeolite by AgNO3 was achieved. Both silver-loaded zeolites showed
antibacterial activities, but commercial zeolite A displayed lower minimum inhibitory concentration value
than wheat hull silica based zeolite.
65
Preparation and Characterization of Antibody-Conjugated Gold Nanoparticles for Targeting Cancer Cells
R. Didarian1 , M. T. Azar1 , E. Piskin2*
1 Hacettepe University, Nanotechnology and Nanomedicine Division, Ankara, Turkey
2 Hacettepe University, Chem.Eng.Dept., and Bioeng.Div., Ankara, Turkey
The aim of this study is to devise and manufacture intelligent inorganic nanoparticles that will be used
imaging and expunging the tumor cells. Cancer is a group of diseases characterized by uncontrolled
growth and spread of abnormal cells and if the spread is not controlled, it can result in death. If
malignancies be detected before cells become cancerous or at an early stage, the disease will be most
treatable. First gold nanoparticles were synthesized about 13-15 nm in diameter. Turkevich method was
used for manufacturing gold nanoparticles. In order to introduce positive charge, cysteamine molecules
have two different end groups (SH and NH2) were coated as self-assembled monolayers (SAMs) onto gold
nanoparticles. These molecules were reacted with the gold surface by SH groups and NH2 was given the
positive charge. Specific receptors exist on tumor cells that can be used to identify them. Antibodies are
connecting specifically to receptors surface on the tumor cells. On the surface of nanoparticles can be
immobilized siRNA for silent therapy and monoclonal antibody for cancer therapy.
66
DNA Vectors: The Application of S/MARs and Minicircles
R.P Harbottle 1,*
1 DKFZ, Heidelberg
Our research is focused on generating novel, next-generation DNA vectors for gene therapy. We have developed a vector system, which is uniquely suited for the genetic modification of cells – it provides persistent expression and episomal maintenance without the use of potentially toxic viral components or the risk of insertional mutagenesis. Additionally, it provides unlimited capacity allowing the unrestricted development of exquisitely designed and endogenously controlled genetic vectors which can comprise entire genomic loci. We have demonstrated the utility of these vectors in vitro, ex vivo and in vivo. The use of eukaryotic chromosomal components allows the design of clinically relevant, episomally sustained replicating DNA vectors that can be used to confer persistent expression of biologically relevant or corrective genes. We will demonstrate the utility of this vector system in a recent study in which we re-introduced the expression of a tumour suppressor gene in a primary cancer cell line and permanently restored its normal biochemistry and reversed its cancer phenotype. We are also involved in the development and application of minimally sized DNA vectors. We have shown that by removing the extraneous bacterial sequences from a vector and utilising minicircles we can improve its efficiency and reduce its toxicity. We have recently shown the utility of this vector system to provide persistent genetic modification and phenotypic correction of dividing cells in culture and for ex vivo application. An alternative application of minimally sized DNA vectors is their application in vivo for gene therapy. In collaboration with Hiu Man Viecelli and Beat Thöny in the Department of Pediatrics, University of Zurich we have successfully utilised minicircle DNA vectors devoid of any viral or bacterial sequences for the long-term treatment of murine phenylketonuria. We designed these vectors to express the murine phenylalanine hydroxylase (Pah) cDNA from a liver-specific promoter coupled to a de novo designed hepatocyte-specific regulatory element, designated P3. These minimally sized DNA vectors were subsequently delivered to the liver by a single hydrodynamic tail vein injection. The DNA vector normalized blood phenylalanine concomitant with reversion of hypopigmentation in a dose-dependent manner for more than 1 year, whereas the corresponding parental plasmid did not result in any phenylalanine clearance. These DNA vectors persisted in an episomal state in the liver consistent with sustained transgene expression and hepatic PAH enzyme activity without any apparent adverse effects. Moreover, 14-20% of all hepatocytes expressed transgenic PAH, and the expression was observed exclusively in the liver and predominately around pericentral areas of the hepatic lobule, while there was no transgene expression in periportal areas. This study demonstrates that minicircle DNA technology has the potential for the genetic treatment of liver diseases.
67
Biolamination for Customised, Rapid Tissue Fabrication: Printer Optional.
R. A. Brown 1,*
1 University College London, UK
A quiet revolution is happening under the umbrella of tissue engineering as it becomes clear that we now
have two distinct approaches to ‘produce’ tissues. Not surprisingly, the route we select has a profound
effect on the technology available. Firstly, and most familiar, is the idea of growing tissues by cultivation
of cells in/on a substrate (often in bioreactors). Secondly we can directly fabricate simple living tissues,
in the same way we ‘make’ cell-phones. In this case there is little or no contribution from the cells, though
they are incorporated as one of the basic building blocks. Fabricating tissues directly is a concept which
has entered largely from public excitement around extensions of 3D bio-printing to incorporate living cells
and proteins into the system. In fact 3D cell-printing is only one of a family of approaches probably better
termed BIO-LAMINATION, in which thin layers (micron scale) of ‘proto-tissue’ are laid down in series to
build up a stack, producing the gross-scale tissue. In fact, although bio-printing provides the popular
image, it is presently far from the most effective form of bio-lamination fabrication, as technical problems
of cell survival and natural matrix polymerisation are complex. Other bio-lamination approaches include
electro-spinning and cell- or matrix-rich layering. Although attractive, the need for bio-printing and
spinning approaches to assemble the X-, Y-, and Z-planes of the 3D tissue simultaneously creates a
technical hurdle. Matrix- and cell- layering techniques avoid this by first mass-fabricating the X-Y plane
layers, then stacking them to give the Z-plane in a separate stage. Cell-rich constructs are fabricated by
expansion of cell sheets on specialised surfaces, matrix-rich X-Y layers by rapid compression of matrix
protein fibres (eg.collagen) to enmesh the cells. Bio-lamination has the capacity to mass produce real
tissues (cells embedded in a native extracellular matrix) in minutes. They can be mass-produced
reproducibly, economically, with simple or complex stacks of heterogeneous layers. They are already
available for use in 3D model tissue drug or disease screening, customised grafts and advanced drug
delivery. However the component laminae are produced, the special and demanding processing features
which they require also represent the great advance of bio-laminated fabrication. These include the need
(i) to incorporate living cells INTO the fabric of the matrix at time zero (so non-lethal processing): (ii) to
fabricate the matrix primarily from a natural (eg protein) fibre network (so no ‘matrix assembly’ stage);
(iii) to provide tight, monitored controls so that each layer is definable/reproducible when mass produced:
(iv) produce a simple (template or model) tissue in minutes or very few hours. Where these criteria can
be met, new opportunities for high impact applications become possible (to be expanded).
68
Alternative Bioprinting Techniques
E. Kayaalp 1 * , E. Pişkin 1
1 Hacettepe University, Bioengineering Division, Ankara, Turkey
In industrial area printing technology is used already in daily life as two dimensional also now three
dimensional printers show up. Whereupon researchers developed bioprinters to build living body part
then bioprinting is a new solution against limitations of tissue engineering’s top-down (traditional)
strategy. With bioprinting, you can print your cells/molecules where you want and how you want,
localisation of printed molecules are arranged by bioprinter, high sensitivity in experiment can be
provided with organization and localisation controls. The most important advantages are abrogating
diffusion and cel-cell interaction limitation and It needs short time and less personel performance. All
those features provide to mimic original tissues in laboratory. Generally all the bioprinters are working
with same strategy. Steps are respectively written as: 1) 3D imaging layer by layer 2) CAD modelling 3)
Blueprint 4) prepare cells and biomaterials what are used for tissue 5) Printing. When bioprinter was
developed, firstly there is one working mechanism which is same with desktop printers. It is thermal ink-
jet based, drop-on-demand strategy. But printing mechanism could be different now. So, Various
alternative bioprinters show up : Valve based bioprinter, Laser assisted bioprinter, Acoustic bioprinter,
developed Ink-jet bioprinters. Ratio of printed cell number and generated stress on cells is important to
build a living tissue. So, our interest is new developed ink-jet systems because of good high-throughput,
high speed, good controlable capacity and less demage on cells. These systems are working as extrusion
based also with pressure or piston aid. At Wake Forest Regenerative Medicine Institute developed ink-jet
bioprinting systems are performed by me to build living engineered tissue. Viability and function of tissues
are at high level close to orijinal ones. If we compare all those different alternative bioprinting techniques,
each one has individual advantages according to what you need for your research. And I show comparing
between Laser assisted bioprinting (LAB) which I worked with before and ink-jet pressure aid bioprinting
with experimental datas. With all experiences and comparing the techniques, although LAB is more
sensitive to print cell one by one, we decided to focus on pressure aid extrusion based technique because
we need high number of cell and result engineered tissue size could be large by pressure aid extrusion
based ink-jet bioprinter. On the other hand, In all the success researches, tissues are printed in-vitro, after
they are matured in tissue culture condition, implanted to body. Correspondingly, our future study’s
question is “ How could we repair tissue as in-situ with bioprinting technique after an injury occured ? “ .
If we are success on that study, army injuries can be treated by new alternative in-situ bioprinting system,
such as loosing skin, muscle, finger etc. Also it is important study for esthetic expectations of patients.
69
Genetically Modified Plants
S. Ari1,2*
1Istanbul University, Department of Molecular Biology and Geneticis, , Vezneciler, İstanbul, Turkey 2Research and Application Center for Biotechnology and Genetic Engineering, İstanbul, Turkey
In 2013, the global area of biotech crops reached to 175.2 million hectares. Biotech crops has grown
impressively for the past 18 years, with almost a remarkable 100-fold increase since the commercialization
began in 1996. Over the last 30 years, the field of genetic engineering has developed rapidly due to the
greater understanding of DNA. The term genetic engineering is used to describe the process by which the
genetic makeup of an organism can be altered using “recombinant DNA technology.” This involves the use
of laboratory tools to insert, alter, or cut out pieces of DNA that contain one or more genes of interest.
Genetic engineering allows the direct transfer of genes of interest between organisms to obtain the
desired agronomic trait. Two primary methods currently exist for introducing transgenes into plant
genomes. The first involves a device called a ‘gene gun.’ The DNA to be introduced into the plant cells is
coated onto tiny particles of gold or tungsten. These particles are then physically shot onto plant cells.
The second method uses a bacterium to introduce the gene(s) of interest into the plant DNA. In the
developed world, it is evident that the use of GM crops has resulted in significant benefits. These “first
generation” crops have proven their ability to increase crop yields, reduce farm costs, increase farm profit,
and help protect the environment. Current research is focused on “second generation” GM crops that will
feature increased nutritional, pharmaceutical and/or industrial traits. These varieties should prove
valuable in countries where millions of people suffer from dietary deficiencies and have difficulties in
accessing vaccines and medicines.
70
Fabrication of Graphene Loaded Porous PLLA/PCL Structures for Bone Tissue Engineering
E.Tekay1, Z.B. Ahi1, Z. Ustundag2, H.M. Aydin3, K.Tuzlakoglu1*
1Yalova University, Department of Polymer Engineering, Yalova, Turkey 2Dumlupinar University, Chemistry Department, 43270, Kutahya, Turkey,
3Hacettepe University, Department of Environmental Engineering, 06800 Beytepe, Ankara, Türkiye,
Carbon- based nanomaterials, especially graphene and its derivates, have gained much attention the use
in tissue engineering applications due to their excellent chemical, electrical and mechanical properties.
Besides the exclusive properties such as easy surface functionalization, maximum surface/volume ratio,
graphene has also showed the positive influence on the mesenchymal stem cell differentiation. In the
present study, we aimed to prepare highly porous biodegradable scaffolds made of PLLA/PCL blend
composed with graphene oxide. Supercritical CO2 method was used to obtain interconnective porous
structure, following salt leaching technique. SEM analysis was use to visualize pore structure and GO
distribution. Well integration of GO into polymeric phase was also confirmed by XRD analysis. The
crystallinity of both PLLA and PCL were decreased in the presence of GO. GO addition also had a positive
influence on compressive strength of the scaffolds, having a compression modulus 0.264MPa and
0.473MPa for unloaded scaffold and 10% GO loaded scaffold, respectively. Thus, the cellular response
studies to these graphene-based constructs are ongoing to prove the success of produced scaffold.
71
Polymeric Nanosystems for Intracellular Delivery of Therapeutics
V. Bulmuş*
Izmir Institute of Technology, Department of Chemical Engineering, Biotechnology and Bioengineering
Graduate Program, Gulbahce, Urla, Izmir, Turkey
We have generated dynamic polymer-RNA conjugates for potential gene silencing applications and pH-
responsive systems combining molecules of biology with synthetic polymers as potential components of
intracellular delivery systems for DNA/RNA therapeutics. Dicer enzyme-labile RNA conjugates of PEG have
been prepared to investigate a new siRNA release strategy. PEG-DsiRNA conjugates having a PEG chain of
2kDa or 10 kDa through 3′-sense strand showed gene silencing activity in human neuroblastoma cells.
Separately, dynamic siRNA conjugates were prepared using a pH-labile sheddable block copolymer (PEG-
b-poly(cholesteryl methacrylate), PEG-b-PCMA) synthesized by RAFT polymerization. The PEG-b-PCMA-b-
siRNA triblock system releases PCMA-b-siRNA segment in acidic and siRNA only in reductive conditions.
Well-defined polyelectrolytes containing molecules of biology such as cholesterol and spermine, have
been prepared via RAFT polymerization as potential components of intracellular drug delivery systems.
Cholesterol containing cationic copolymers were prepared via RAFT polymerization of dimethylamino
ethylmethacrylate and cholesteryl methacrylate. Cellular internalization studies suggested that siRNA
polyplexes of these copolymers efficiently escaped the endolysosomal pathway and released siRNA into
the cytoplasm. Recently, spermine-like polymers were prepared as potential endosomal escaping agents.
For this purpose, a new monomer (AEAEMA) was synthesized and polymerized via RAFT polymerization.
P(AEAEMA) was found to possess proton sponge capacity comparable with PEI.
72
Mechanical Signals and Cellular Functions
Y.F. Missirlis*
University of Patras, Laboratory of Biomechanics & Biomedical Engineering, Patras, Greece
Solid mechanical and fluid mechanical signals are ever-present in all living organisms across all pertinent
time and size scales. The fate of cells as to their differentiation, growth, migration or apoptosis depends
to a large extent on the mechanical information they sense, integrate and respond to. How the cells sense
and transmit forces from their environment to their nucleus is under intense investigation in recent years,
but we are still far from having a clear picture of the associated events. In this presentation, several
examples will be given from the literature and from our lab, such as cancer, immune cells, mesenchymal
cells, endothelium et al, to show the widespread influence of different mechanical signals to different
cellular functions.
73
Detection of Pathogens in Food and Environment
F. Yeşim Ekinci*
Yeditepe University, Department of Food Engineering, Genetic Engineering, Bioengineering, Kadiköy, İstanbul, Turkey
The transmission of pathogens via food or environment can pose a significant threat to human health,
leading to a critical necessity for the rapid, reliable and early detection of pathogens. Traditional analysis
of pathogenic microorganisms is often time-consuming because of the need for growth in culture media,
followed by isolation and biochemical and/or serological identification. Advances in molecular biology,
immunology, automation, and computer technology continue to yield improved (fast, sensitive and
convenient) methods for detection, identification and quantification of specific pathogens. Recent rapid
methods generally comprise two stages: In the first stage, the target is captured and discriminated from
the remaining material in the sample. This can be done by using surface or whole-cell recognition
methods, including immunoassay techniques and molecule-specific probes; by using nucleic acid
methods, including polymerase chain reaction (PCR), quantitative PCR (Q-PCR), nucleic acid sequence-
based amplification and microarrays; or by using enzyme/substrate methods, including utilization of
chromogenic or fluorogenic substrates. In the second stage, microorganisms are detected, by using
optical, electrochemical or piezoelectric technologies to quantify the captured, tagged or amplified
material. The talk will review most recent techniques in rapid food and environment pathogen detection,
and discuss advantages and disadvantages of each.
74
Control of Cell Alignment within Tissue Engineering 3D Hydrogels and in Injury Models
Y. Yang*
Keele University, Institute of Science and Technology in Medicine, School of Medicine, Stoke-on-Trent, UK
Hydrogels are a popular choice for use as three dimensional (3D) scaffolds in tissue engineering. They
have exceptional biocompatibility and simple processing methods. However, they rarely induce tissue-
like organization of cells. There was no effective and practical technique to promote specific, regional
organization of cells within 3D hydrogels, necessary to mimic the unique, heterogeneous arrangement of
cells and extracellular matrix (ECM) exhibited by specific soft tissues. We develop a facile technique to
controls the cell attachment and alignment processes in a planar fashion, within 3D hydrogels in
spatiotemporal accuracy. The angle of individual cell orientation within a specific plane and the respective
alignment angle between planes can be user-controlled, with a high degree of accuracy and
reproducibility. The cells on each plane have sufficient mobility for migration along and between the
planes. The technique has been used to construct corneal stromal layer and annulus fibrosus (AF) lamella
with orthogonally arranged keratocytes and the alternating 60o arranged AF cells achieved respectively.
The advantage of using this technique to promote the repair and regeneration of axons in a spinal cord
injury model have been observed.
75
Novel PLLA/PCL Films with Natural Antibacterial Extracts for Guided Tissue Regeneration
Z.B. Ahi1*, N.Z. Renkler2, E.Tekay1, M. Gül Şeker3, K.Tuzlakoglu1
1Yalova University, Department of Polymer Engineering, Yalova, Turkey 2Ege University, Bioengineering Department, İzmir, Turkey
3Gebze Institute of Technology, Department of Molecular Biology and Genetics, Kocaeli, Turkey
Guided tissue regeneration (GTR) therapy becomes a most favored approach in the treatment of
periodontal diseases. There are several non-degradable and biodegradable membranes are available to
function as a barrier membrane for this treatment. Considering the high infection risks in the oral
environment, the use of an antibacterial membrane seems to be essential. To avoid the antibiotic use,
natural extracts can be a good alternative for that. In this study, we reported a new antibacterial film, the
films composed of poly-L-lactide/polycaprolactone (PLLA/PCL) and ethanol extracted propolis (EEP). The
films with different PLLA/PCL ratio (100/0, 90/10, 80/10, 70/10, 0/100 w/w) were prepared with the pre-
optimized EEP amount by solvent casting technique. The films without EEP were used as controls for all
characterization tests. The mechanical properties of the films were characterized by tensile test, thermal
behaviors were characterized by Differential Scanning Calorimetry (DSC) and their surface morphology
was investigated by Scanning Electron Microscopy (SEM). The surface topography of the scaffolds was
completely changed in the presence of propolis, having a self-patterning honeycomb-like structures. The
presence of EEP also affected the mechanical characteristics of the blend films as well as their thermal
behaviors. Tensile test revealed that in the presence EEP, the films become more pliable with an elastic
modulus in the range of 122-336 MPa. The antibacterial properties of the samples were evaluated by zone
inhibition tests aganist S. aureus. All the film with propolis showed zone inhibition between 13-17mm
while there was no in control samples. Thus, all these results suggest that addition of propolis in the
PLLA/PCL blend films resulted in the achievement of better plasticity that permits bending, contouring
and adaptation to any periodontal defect site in addition to antibacterial potency against Gram negative
bacterial strain.
76
Utilization of Biodiesel by-product Crude Glycerol for Lactic acid Production by Recombinant Yeast
L. Mahmoudi Azar2, F. Ayas1, I.B. Çam1, S.Yılmaz1, E. Pişkin2, M. İnan1*
1 Akdeniz University, Department of Food Engineering, Antalya, Turkey
2 Hacettepe University, Department of Bioengineering, Faculty of Science, Ankara, Turkey. * [email protected]
Lactic acid production from renewable sources gained much attention, recently. Lactic acid is a raw
material that is used in the manufacture of bioplastics. It has a high potential of using in the field of
controlled drug delivery, implantable composites and bone fixation parts. Industrial scale production of
lactic acid can be feasible with cheap carbon sources by fermentation. The cost of raw material is very
significant in lactic acid production. The use of inexpensive substrates such as crude glycerol as by-product
of biodiesel has a potential to reduce cost of lactic acid production. In this study, Pichia pastoris expressing
bovine lactate dehydrogenase was used to produce lactic acid. These recombinant clones were obtained
from previous studies. After inoculating on YPD media, the yeast cells were grown in rich media with
different carbon source such as glucose, commercial grade glycerol and crude glycerol for about 48 hours
in shake flasks. Lactic acid, glucose and glycerol concentrations were measured by HPLC from the samples
taken in 12, 24, 36 and 48 hours. The lactic acid produced from recombinant P. pastoris grown on glucose,
commercial grade glycerol and crude glycerol reached highest amount of 28.78, 17.5 and 18.98 g/L,
respectively. In conclusion, crude glycerol as a carbon source in lactic acid fermentation can be used as an
alternative of pure glycerol.
77
Nanomaterials Based Electrochemical Biosensors
A. Erdem*
Ege University, Faculty of Pharmacy, Analytical Chemistry Department, Bornova, 35100 Izmir, Turkey
There have been many technological advances progressed for the development of biosensors to detect
the interactions of nucleic acids, or proteins, and also the recognition events of biomolecules in solution
and at the solid substrates. The growth of highly developed biosensors could effect significantly the areas
of genomics, diagnostics, drug discovery and environmental monitoring. The advanced biosensors
combined with graphene, carbon nanotubes, nanoparticles, dendrimers, nanowires, nanorods, and other
nanomaterials have recently received a considerable attention. Different nanomaterials combined with
electrochemical biosensor technology presented herein for biomolecular recognitions bring some
important advantages; more sensitivity and selectivity, and it also can eliminate advanced surface
modification by resulting in a greatly simplified protocol.
78
Microfluidic Bio-Particle Manipulation
B. Çetin*
Bilkent University, Microfluidics & Lab-on-a-chip Research Group, Mechanical Engineering Department
İhsan Doğramacı, 06800 Ankara, Turkey
Lab-on-a-chip (LOC) devices are microfluidic platforms on which one can handle chemical and biological
analyses, point-of-care testing, clinical and forensic analysis, molecular diagnostics and medical
diagnostics for biological, biomedical and chemical applications. LOC devices can perform the same
specialized functions as their room-sized counterparts. Chips can perform clinical diagnoses, scan DNA,
run electrophoretic separa-tions, act as microreactors, detect cancer cells and identify bacteria and
viruses. On a single chip, hundreds of different reactions and/or analyses can be performed at the same
time through hundreds of different reactions and/or analyses can be performed at the same time through
hundreds of parallel microchannels. For chemical, biological and biomedical analysis in microfluidic
systems, there are some fundamental operations such as separation, focusing, filtering, concentration,
trapping, sorting, detection, counting, washing, lysis of bio-particles, and PCR-like reactions. The
combination of these operations led to the complete analysis system or LOC system for a certain
application. Manipulation of the bio-particles is the key ingredient for the many aforementioned
processes. Therefore, microfluidic bio-particle manipulation has attracted a significant attention from the
academic community. Considering the size of the bio-particles and the throughput of the practical
applications, manipulation of the bio-particles is a challenging problem. Many research groups and
scientists have proposed utilizing different techniques to manipulate bio-particles such as hydrodynamic-
based, electrokinetic-based, acoustic-based, magnetic-based, optical-based etc. In this talk, different
techniques and the comparison among them will be discussed. Some recent biotechnology applications
regarding the microfluidic bio-particle manipulation will also be presented. Challenges regarding the
design, fabrication and integration of these systems will be discussed. The recent research projects within
the Bilkent University Microfluidics and Lab-on-a-chip Research Group will also be presented.
79
Interaction of Nondegradable, Stiff Hydrophobic Polymers with Human Osteoblast Like Cells
O. Hasturk1, 2, M. Ermis1, 3, P. Chen 5, U. Demirci 5, V. Hasirci1, 2, 3, 4*
1 METU, BIOMATEN, Center of Excellence in Biomaterials and Tissue Engineering, Ankara, Turkey 2 METU, Department of Biotechnology, Graduate School of Natural and Applied Sciences, Ankara, Turkey
3 METU, Department of Biomedical Engineering, Graduate School of Natural and Applied Sciences, Ankara, Turkey 4 METU,Department of Biological Sciences, Faculty of Arts and Sciences, Ankara, Turkey
5 Stanford University, Bio-Acoustic MEMS in Medicine (BAMM) Lab, Department of Radiology, School of Medicine, CA, 94304, USA
Cell adhesion is one of the most important processes in cell-material interactions. All the other cellular
processes including proliferation, differentiation, mobility and ECM deposition depend on the initial
attachment phase. On the other hand, the extent of cell adhesion depends heavily on the chemical and
physical properties of the substrate. Studies show that in general, cells adhere better on surfaces with
contact angles in the range 60-80° and most commercial tissue culture surfaces have similar contact
angles. In this study poly(methyl methacrylate) (PMMA) was used to study the behavior of human
osteoblast-like cells on these stiff substrates decorated with micro level patterns. The static contact angle
of PMMA was found to be 85.17° (±2.2), indicating a very hydrophobic surface when smooth. It is known
that micropatterns on the surface decrease surface wettability and increase water contact angles further.
PMMA surfaces were decorated with square prism posts with top surface areas of 4x4 μm2, 8x8 μm2 and
16x16 μm2 and were seeded with primary human osteoblast like cells (HOBs) isolated from donated tissue.
Their interaction was studied using SEM and CLSM for cell attachment, spread and distribution of focal
contact points. HOBs were observed to attach, spread and align on and among these stiff PMMA
microposts. Cytoskeleton and nuclei were observed to be located in between and on top of the pillars and
deformation of cell nuclei were observed as a result of these interactions. Depending on the micropost
size and interpost spacing, the morphology of the cells changed. It was concluded that these stiff and
hydrophobic substrates decorated with micropatterns could guide cell adhesion and spreading which
could prove to be important for tissue engineering.
80
Electrospun Poly(ɛ-caprolactone) Membranes Loaded with Ag Nanoparticules
Ö. Eğri1, D. Kong2, E. Pişkin3,4*
1Gaziosmanpaşa University, Faculty of Engineering and Natural Sciences, Department of Bioengineering, Tokat, Turkey
2Nankai University, Department of Life Sciences, The Key Laboratory of Bioactive Materials, Tianjin, China 3Hacettepe University., Chemical Engineering Department and Bioengineering Division, Ankara, Turkey
4Biyomedtek Society of Biomedical Technologies, Ankara, Turkey
In this study, Poly(ɛ-caprolactone) (PCL) solutions with different concentrations were electrospun to form
membranes in the presence of silver nanoparticles (NPs) with different ratios. At the same time, various
membranes were electrospun at suitable moist and flow-rate conditions from PCL solutions with no NP
content. These blank membrane samples were then swollen with alcohol solution containing different
amounts of NPs in order to allow silver NPs to penetrate within these membranes. All membranes were
evaluated through SEM images. Membranes electrospun from solutions of PCL containing silver NPs were
determined to lose active properties by sinking into the nanofibers formed during electrospinning process.
Membranes loaded with silver NPs by swelling were determined to have NPs in the outermost layers, but
as the NPs content in the swelling solution increased, agglomeration of NPs around the nanofibers occurs.
By the experiments conducted in this study, silver nanoparticles loading conditions to electrospun PCL
membranes were optimized for loading without any loss of antibacterial activity and agglomeration of
silver NPs.
81
Effect of High Shear Mixing on the Thermal Behavior of Starch-g-PLA Blends
K. Salimi1, S. Eğri2 and E. Pişkin1*
1Hacettepe University, Department of Chemical Engineering and Bioengineering Division, Centre for
Bioengineering and Biyomedtek/Nanobiyomedtek, Beytepe, Ankara, Turkey. 2Gaziosmanpaşa University, Department of Bioengineeering, Tokat, Turkey.
The blending of thermoplastic starch (TPS) with L-lactic acid (LA) could be an interesting way to produce
new environmentally friendlier/biodegradable starch-based plastics. In this work, different ratios of corn-
starch and L-lactic acid were mixed under Turbo-Mixing system to produce Starch-g-PLA copolymers.
After pelletization, granules were melt blended by twin extrusion to produce test specimens and
investigate the effect of shear heating and melt extrusion on the starch and final Starch-g-PLA properties.
A range of blends were studied with lactic/starch content ratios varying from 0.13 to 0.55. The chemical
structure of graft copolymers were characterized by FTIR, ¹³C CP/MAS NMR, DSC-TGA-DTG and XRD
analysis methods. Thanks to the thermal properties of each polymeric components, we analyzed the
blends’ thermal behavior by varying each component concentration. It is clear that in the presence of a
continuous shear rate by Turbo-Mixing energy, 20% aqueous solution of LA and increasing in the amount
of LA in polymerization media caused to the irreversible gelatinization of starch granules and changes
included the swelling of starch granules caused to an amorphous graft copolymer with the grafting of LA
on the starch backbone.
82
Surface Plasmon Resonance Based Biosensor for Determination of Anti-CCP Antibodies
H. Dibekkaya1, Y. Saylan2*, F. Yılmaz3, A. Denizli2
1Hacettepe University, Division of Bioengineering, 06800, Ankara, Turkey 2Hacettepe University, Department of Chemistry, 06800, Ankara, Turkey
3Abant İzzet Baysal University, Bolu, Turkey
Surface plasmon resonance (SPR) biosensors use a special mode of the metal-dielectric waveguide to
measure changes in the refractive index due to the biomolecular interaction occurring at the surface of
the SPR sensor. SPR biosensors show the most advanced and mature label-free optical biosensor
technology. Because of unique properties of SPR biosensors, such as real-time measurement, high
specificity and sensitivity, no need to labeling, the applications of them have been getting more popular
for investigation of several analyte molecules. Recently, MIPs are used for creation of biorecognitive
surfaces on the SPR biosensors. Molecularly imprinted polymers (MIP) are materials that are easy to
prepare, less expensive, stable, have talent for molecular recognition and also can be manufactured in
large quantities with good reproducibility. Therefore, MIPs can be considered as artificial recognition
media. Molecular recognition-based adsorption techniques have received much attention in several fields
because of their high selectivity for target molecules. Rheumatoid arthritis (RA) suffers up to 1% of the
world's population, affecting females to a greater extent (3–5 fold) than males. Most recently the
diagnosis of RA is made through evaluation of clinical symptoms, autoantibody serology including
rheumatoid factor (RF), and acute phase reactants such as C-reactive protein (CRP), both of which are
moderately sensitive but lack clinical specificity and do not detect early asymptomatic disease. Anti-cyclic
citrullinated peptide (anti-CCP) antibodies are IgG autoantibodies which recognize citrullinated peptides
and offer improved specificity in early diagnosis of RA compared to RF. Anti-CCP antibodies are among
the most specific autoantibody systems described in RA and are believed to play a role in disease
pathogenesis. In this study, we have focused our attention on combining of molecular imprinting into
nanofilms and SPR biosensor approaches and producing SPR biosensor for anti-CCP, chosen as model
protein, using anti-CCP imprinted nanofilms. For this aim, anti-CCP imprinted SPR biosensor was
characterized by Fourier transform infrared spectroscopy, atomic force microscopy, and ellipsometry.
Association kinetics analysis, Scatchard, Langmuir, Freundlich, Langmuir–Freundlich isotherms were
applied to data. The nonimprinted biosensors were also prepared to evaluate the selectivity of the
imprinted biosensor. Finally, the biosensor is used for five adsorption–desorption–regeneration cycle and
it gives reproducible response.
83
Microfludic device design for diagnosis of heart attack
E.Haberal1,Y.Koçak1, M.Kocakulak1*
1Baskent University, Department of Biomedical Engineering, Ankara, Turkey
Coronary heart disease is the leading cause of morbidity and mortality among adults in Turkey. It is crucial
to diagnose myocardial infarction especially after the coronary bypass surgery. American Heart
Association and European Society of Cardiology emphasize that troponins can be used as biochemical
markers to diagnose myocardial infarction. The goal of this research is to develop a highly sensitive and
rapid biosensor system that can measure troponin T levels in a rapid, sensitive and easy way. QCM crystals
were chemically modified to measure changes in absorbed mass on the surface and were used to detect
the amount of the troponin concentrations. In order to form self – assembled monolayers on gold QCM,
crystals were immersed into MPA solution. Flow cell was cut from PMMA using laser cutter and assembled
using double sided adhesive. Silver conductive paint was used for electrode connections for QCM with the
oscillator and frequency counter. The MPA modified crystal was mounted in the flow cell with only
one side exposed to the solution, and the analytical response was evaluated in the flow cell. The
detecting system was operated in continuous flow mode aided by a peristaltic pump. Flow cell was
filled with EDC/NHS solution and terminal carboxylic groups were converted to active NHS esters than
troponin antibody was applied on surface. QCM crystals with immobilized anti-cTnT were tested using
different concentrations of troponin proteins. Frequency values of the sensor system were changing
proportional to the amount of troponin concentration in the sample, indicating that troponin proteins
attach to the surface of the QCM. The sensor was regenerated online by the solution of 3 mol/L Urea
while preserving the activity of the immunosensor.
84
Advanced Electrochemical Biosensors for Detection of Pathogens and Toxins
A. Erdem*
Ege University, Faculty of Pharmacy, Analytical Chemistry Department, 35100 Bornova, Izmir, TURKEY
The fast, reliable, sensitive and selective monitoring of biological toxins and food pathogens are on the
practical frontier to keep public health and food safety from foodborne illness and bioterrorism. The
detection protocol for pathogens and toxins should be sensitive, rapid, and easily applicable to diverse
sorts of diagnostic samples; because of this reason, there is an urgent need to speed up the recognition
and monitoring scheme of numerours toxins and pathogens. Numerous technological improvements have
been progressed for the development of novel biosensors to monitor interactions and recognition events
of biomolecules. Advanced electrochemical biosensors can offer great promise for exploring a difference
in various biointeraction process occurred in solution and also at the sensor surface. The growth of these
electrochemical biosensors could effect significantly the areas of genomics, diagnostics, drug discovery
and also, environmental monitoring on screening of selected toxins and pathogens.
85
Machining-Based Fabrication of Microfluidic Devices for Biotechnology
B. Çetin*
Bilkent University, Microfluidics & Lab-on-a-chip Research Group, Mechanical Engineering Department
İhsan Doğramacı 06800 Ankara, Turkey
Microfluidics and lab-on-a-chip technology offers unique advantages for the next generation devices for
biotechnology applications. When the fabrication of the microfluidic devices is concerned, there are
basically two common approaches: direct substrate manufacturing (photolithography, etching, laser
ablation etc.) and mold-based techniques (hot embossing, injection molding or soft-lithography).
Photolithography has good ability to manufacture very small and complicated microchannel structures,
but it usually involves multi-step processes which take considerable time and specific chemical
requirements especially for etching steps in high tech facilities such as a clean-room environment. One
alternative method to fabricate the microfluidic device is to use mechanical micromachining (i.e. CNC-
machining) either for direct substrate manufacturing or for the fabrication of the mold. For direct
substrate manufacturing, the limits of the process is constrained by the size of the milling tool which may
lead to unsatisfactory end-product for microfluidic applications. However, for the fabrication of the mold,
the process is limited by the xyz-accuracy of the tool-positioner of a CNC-machine since the negative of
the microfluidic structure is fabricated as the mold. With today's technology, by using magnetic bearings
for their positioning systems, the xyz-accuracy of a conventional CNC-machines are around 5 micrometer.
Therefore, a mold can be fabricated using mechanical machining within couple of hours without any need
for clean-room equipment within the desirable accuracy limits for microfluidic devices. Moreover, CNC-
machining can generate 3D structures without any difficulty. In this talk, different aspects of machining-
based microfluidics devices will be discussed. Moreover, some recent microfluidic devices which have
potential to be used in biotechnology based applications and were fabricated by machining within Bilkent
University Microfluidics & Lab-on-a-chip Research Group will be demonstrated.
86
Nanofabrication and Characterization of Poly(MA-alt-1-octadecene)-g-PLA Layered Silicate Nanocomposites
K. Salimi1, Z. M. O. Rzayev2 and E. Pişkin1*
1Hacettepe University, Department of Chemical Engineering and Bioengineering Division, centre for
Bioengineering and Biyomedtek/Nanobiyomedtek, Beytepe, Ankara, Turkey. 2Hacettepe University, Institute of Graduate Studies in Science, Division of Nanotechnology and Nanomedicine,
Beytepe, Ankara, Turkey.
Novel bioengineering functional copolymer-g-biopolymer-based layered silicate nanocomposites were
fabricated by catalytic interlamellar bulk graft copolymerization of L-lactic acid (LA) monomer onto
alternating copolymer of maleic anhydride (MA) with 1-octadecene as a reactive matrix polymer in the
presence of preintercalated LA…organo-MMT clay (reactive ODA-MMT and non-reactive DMDA-MMT)
complexes as nanofillers and tin(oct)2 as a catalyst under vacuum at 80°C. Various characterization
methods such as FT-IR spectroscopy, X-ray diffraction (XRD), thermal (DSC and TGA-DTG), SEM/TEM were
employed to understand the mechanism of in situ processing, interfacial interactions and nanostructure
formations. It was found that in situ graft copolymerization occurred through the following steps: (i)
esterification of anhydride units of copolymer with LA; (ii) intercalation of LA between silicate galleries;
(iii) intercalation of matrix copolymer into silicate layers through in situ amidization of anhydride units
with octadecyl amine intercalant; and (iv) interlamellar graft copolymerization via in situ
intercalating/exfoliating processing. It was found that the main properties of nanocomposites
significantly depend on the origin of MMT clays and type of in situ processing.This developed approach
can be applied to a wide range of anhydride containing copolymers and graft copolymers of MA to
synthesize new generation of polymer-g-biopolymer silicate layered nanocomposites and nanofibers for
nanoengineering applications.
87
Gene Transfer to Animal Cells
S. Odabas1*
1 Ankara University, Department of Chemistry, Biochemistry Division and
Ankara University Stem Cell Institute, Ankara, TURKEY
Gene transfer to animal cells was first achieved in 1960s. Initial efforts was only performed for explaining
the functions and the role of the genes but nowadays, it become a fundamental technique for genetic
manipulation, targeted gene therapy and cell mediated gene therapy. There are several available
opportunities for the transfection of an animal cells: using a biological viral vectors (Adeno-associated,
retrovirus etc.) or using a chemically modified non-viral vectors (cationic polymers, liposomes etc.) or
physical delivery methods like electroporation, magnetic impulse or gene gun. Still, biocompatibility of
the vectors, efficiency of the transfection and long term stability of the delivered genes are the major
problems for gene transfers into animal cells especially primary cells harvested for the therapeutic
purpose.
88
Mineralized Chitosan Scaffolds for Bone Tissue Engineering Applications
S. Ucar1,2, M. Ermis4,2, V. Hasirci3, 4, 2, N. Hasirci1,2,4 *
1Middle East Technical University (METU), Department of Chemistry, Faculty of Arts and Sciences, Ankara, Turkey 2METU,BIOMATEN, Center of Excellence in Biomaterials and Tissue Engineering, Ankara, Turkey
3METU,Department of Biological Sciences, Faculty of Arts and Sciences, Ankara, Turkey 4METU,Department of Biomedical Engineering, Graduate School of Natural and Applied Sciences, Ankara, Turkey
Chitosan scaffolds were prepared to use as scaffolds in bone tissue engineering applications. Wet spinning
technique was employed to obtain porous microfibrous structures, and the scaffolds were coated with
minerals via incubation of them in concentrated simulated body fluid (SBF-5) for different periods (CH-
BM/2 for 2 days and CH-BM/7 for 7 days). Calcium phosphate minerals formed on the scaffolds were
characterized by energy dispersive X-ray analysis (EDX) and Ca:P ratios were found to be 1.80 (± 0.12) and
1.54 (± 0.08) for CH-BM/2 and CH-BM/7, respectively. Compression moduli (modulus after pore collapse,
E2) were 0.344 MPa (± 0.03) for pure chitosan, 3.64 MPa (± 0.145) for CH-BM/2, and 7.07 MPa (± 0.112)
for CH-BM/7. In vitro studies were carried out using Saos2 cells for their osteoblast-like properties. The
cells did not show a strong attachment on pure chitosan fibers, but the presence of calcium phosphate
coat on the CH-BM/2 and CH-BM/7 scaffolds improved attachment. Best results were observed with CH-
BM/2 samples which were in agreement with the literature reporting that higher Ca:P ratios result in
better cell adhesion. The scaffolds were then loaded with a model antibiotic (Gentamicin) by applying
vacuum-pressure cycle. Release of drug from the scaffolds was examined spectrophotometrically in
phosphate buffered saline (PBS). Release was significantly faster from the calcium phosphate coated
samples due to the decreased hydrogen bonding between chitosan and Gentamicin. Meanwhile, effect of
Gentamicin released from the scaffolds on E.coli was examined by using disk diffusion technique and all
the antibiotic loaded scaffolds were found to have similar growth inhibition zones with the Gentamicin
tablet. Our results showed that these chitosan based scaffolds with their controlled antibiotic delivery
feature have a significant potential in bone tissue engineering applications.
89
Measurement of Protein Adsorption on Oxygenator Fibers with Qcm Sensor
E.Haberal1,T.Dutsağ1,E.Özcan1, M.Kocakulak1 *
1Baskent University, Department of Biomedical Engineering, Ankara, Turkey
During the open heart surgery, heart and the lungs must be temporary deactivated. Meantime the vital
functions of the patient such as circulatory and respiratory has been provided by heart-lung pump. In
order to carry on the vital functions, the oxygenater provides necessary oxygen to blood and perfusion of
organs. The contact of the blood with the artifical surface, systemic inflammation, bleeding tendency and
can cause organ losses.To prevent these problems, a variety of types of coatings have been developed.
PMEA-coated and polypeptide fibers are the coatings which are known as new types of coatings. The
interaction of these surfaces with blood proteins help to improve the bio compatibility studies. Tt was
intended to observe compatibility of oxygenator fibers used in cardiopulmonary machines with blood
proteins for different coatings in concentration, time and temperature conditions respectively, interpret
the data obtained through these observations and correspondingly help the studies conducted to develop
fibers that oxygenate blood in maximum level for oxygenators used in open heart surgeries. It is seen that
when polypeptide and PMEA are compared, compatibility of polypeptide coating and protein adsorption
level are lesser than PMEA for values obtained in different concentrations and experiments conducted
using different temperatures. According to the obtained data, blood protein adsorbtion on polypeptide
coated oxygenator fibers is lower than PMEA coated fibers.
90
Protein Purification with Magnetic Nanoparticles on Immobilized Metal Affinity Chromatography
Y. Saylan1,S. Akgönüllü1*, H. Yavuz1, A. Denizli1
1Hacettepe University, Department of Chemistry, 06800, Ankara, Turkey
Interferons are biologically active and very important proteins for the immune system of mammalian species. They can be classified as a member of large group of glycoproteins and were named as “interferon” because of their ability to interfere with viral proliferation. Beside the uses of interferons in treatments of kidney cancer, multiple myeloma, carsinoid, lymphoma and leukemia, especially recombinant human interferon-, that comprises a family of extracellular signaling proteins with antiviral, antiproliferating and immunomodulatory activities, is especially used for the treatment of AIDS-related Kaposi’s sarcoma, hairy cell leukemia, and chronic hepatitis B and C. Therapeutic value of interferons against certain types of tumors such as brain tumors and malignant melanomas caused both increasing interest in these proteins and more focusing on investigations aimed to obtain treated and purified interferons. The purification of human interferons from various sources has been attempted by a variety of methods including metal-chelation, precipitation, cation or anion-exchange, gel filtration, hydrophobic and immunoaffinity chromatography over many years. In recent years, magnetic nanoparticles have many important applications of biotechnological applications as sorting or separating cells, proteins, and DNA, enzyme immobilization, protein purification, magnetic resonance imaging contrast agent, medical diagnosis and controlled drug delivery. Magnetic nanoparticles have several advantages as support materials such as good mass-transfer properties, easy recovery and reuse of purification proteins, and also got a large specific surface area, which can be used for the purification of proteins. Immobilized metal affinity chromatography (IMAC), adsorption of proteins is based on the interaction between an immobilized metal ion and electron donor groups located on the surface of proteins. IMAC is a powerful technique and also suitable for a kind of purposes, containing analytical and preparative purification of proteins, as well as being a valuable tool for studying surface accessibility of certain amino acid residues. The aim of this study is synthesis magnetic nanoparticles for purify interferon. For this purpose, N-methacryloly-(l)-cysteinemethylester (MAC) containing 2-hydroxyethyl methacrylate (HEMA) based magnetic nanoparticles were synthesized by using micro-emulsion polymerization technique for templating interferon via metal chelation. The obtained nanoparticles were characterized with Fourier transform infrared spectroscopy (FTIR-ATR), transmission electron microscopy (TEM), zeta-size analysis and electron spin resonance (ESR) spectroscopy. After that, they were used for interferon separation from aqueous solution to evaluate/optimize the adsorption condition. Hereby, the effecting factors such as concentration, pH, ionic strength, temperature, and reusability were evaluated. The selectivity of the imprinted materials were also investigated by using immunoglobulin G and myoglobin as competitors. As the last step, the materials were used for interferon separation from human plasma and purity of the interferon were determined with sodium dodecy sulfate-polyacrylamide gel electrophoresis.
91
Using of Different Clays as Catalyst-nanofillers in Interlamellar Graft Copolymerization of L-lactic acid onto Poly(MA-alt-1-octadecene)
K. Salimi1, Z. M. O. Rzayev2 and E. Pişkin1*
1Hacettepe University, Department of Chemical Engineering and Bioengineering Division, centre for Bioengineering and Biyomedtek/Nanobiyomedtek, Beytepe, Ankara, Turkey.
2 Hacettepe University, Institute of Graduate Studies in Science, Division of Nanotechnology and Nanomedicine, Beytepe, Ankara, Turkey.
In this work, nanocomposites were prepared by in situ graft copolymerisation of L-lactic acid (LA) onto
poly(maleic anhydride-alt-1-octadecene) in the presence of Na+-montmorillonite (Mt), Ag+-Mt and
octadecyl amine-Mt (ODA) nanofillers using a specially constructed vacuum micro-reactor with Dean-
Stark unit at 80°C. It was observed that inorganic and organic clays executed the dual functions as catalyst
of interlamellar graft copolymerisation and nano-filler in formation of clay polymer nanocomposites
(CPNs). This new approach allow us to realize the grafting and graft copolymerization without use of
hazardous tin(oct)2 catalyst. The surfactant matrix copolymer provides the first step of grafting via ring
opening monoesterification of anhydride units with LA monomer. The catalytic activity of the positively
charged clays and their LA preintercalated complexes as a function of phase separation time, strongly
depends on the particle parameters (zeta-size and zeta-potential) of the used clay systems and changed
in the following range: organoclay < Na+-Mt < Ag+-Mt. The obtained graft copolymer/clay nanohybrids
were characterised by FTIR, ¹H and ¹³C NMR, DSC-TGA-DTG, XRD and SEM-TEM analysis methods. Better
results were obtained for the copolymer-g-biopolymer/reactive organoclay nanocomposites. It was
concluded that this versatile and green synthetic method can utilize for a wide range of anhydride-
containing alternating, random, graft and block functional copolymers as matrix polymers and their
silicate layered nanocomposites.
92
Novel PLLA/PCL Films with Natural Antibacterial Extracts for Guided Tissue Regeneration
Z.B. Ahi1, N.Z. Renkler2, E.Tekay1, M. Gül Şeker3, K.Tuzlakoglu1*
1Yalova University, Department of Polymer Engineering, Yalova, Turkey
2Ege University, Bioengineering Department, İzmir, Turkey 3Gebze Institute of Technology, Department of Molecular Biology and Genetics, Kocaeli, Turkey
Guided tissue regeneration (GTR) therapy becomes a most favored approach in the treatment of
periodontal diseases. There are several non-degradable and biodegradable membranes are available to
function as a barrier membrane for this treatment. Considering the high infection risks in the oral
environment, the use of an antibacterial membrane seems to be essential. To avoid the antibiotic use,
natural extracts can be a good alternative for that. In this study, we reported a new antibacterial film, the
films composed of poly-L-lactide/polycaprolactone (PLLA/PCL) and ethanol extracted propolis (EEP). The
films with different PLLA/PCL ratio (100/0, 90/10, 80/10, 70/10, 0/100 w/w) were prepared with the pre-
optimized EEP amount by solvent casting technique. The films without EEP were used as controls for all
characterization tests. The mechanical properties of the films were characterized by tensile test, thermal
behaviors were characterized by Differential Scanning Calorimetry (DSC) and their surface morphology
was investigated by Scanning Electron Microscopy (SEM). The surface topography of the scaffolds was
completely changed in the presence of propolis, having a self-patterning honeycomb-like structures. The
presence of EEP also affected the mechanical characteristics of the blend films as well as their thermal
behaviors. Tensile test revealed that in the presence EEP, the films become more pliable with an elastic
modulus in the range of 122-336 MPa. The antibacterial properties of the samples were evaluated by zone
inhibition tests aganist S. aureus. All the film with propolis showed zone inhibition between 13-17mm
while there was no in control samples. Thus, all these results suggest that addition of propolis in the
PLLA/PCL blend films resulted in the achievement of better plasticity that permits bending, contouring
and adaptation to any periodontal defect site in addition to antibacterial potency against Gram negative
bacterial strain.
93
Cationic Chitosan/Polycaprolactone (Cs/PCL) Hybrid Scaffolds Application Capability as ‘’Smart Labels’’ in the Food Packaging Systems
A. Ebrahimi 1.2, E. Piskin 1*
1 Chemical Engineering Department and Bioengineering Division, Centre for Bioengineering and Biyomedtek/
Nanobiyomedtek Hacettepe University, Beytepe, 06800, Ankara, Turkey. 2 Nanotechnology and Nanomedicine Div., Hacettepe University, Beytepe, Ankara, Turkey.
In this study, cationic chitosan/polycaprolactone (Cs/PCL) hybrid scaffolds were successfully prepared
with several different electrospnning method and the most proper method was selected to obtain cationic
chitosan/polycaprolactone nanofiber films for application as a smart labels in the food packaging systems.
PCL was synthesized in the presence of ɛ-caprolactone and stannous 2-ethyl hexanoate as monomer and
catalyst, respectively. Subsequently, chitosan-graft-poly (ɛ-caprolactone) was synthesized successfully in
acetic acid under N2 atmosphere. Synthesized PCL and Cs-PCL were characterized by FTIR and HNMR.
Cationic electrospun scaffolds were prepared with 4 different method. In the first method after blending
of chitosan and PCL scoffold was prepared by electrospinnig method. In second method, chitosan-graft-
poly (ɛ-caprolactone) and polycaprolactone (CS-PCL/PCL) were blended then nanofibers were prepared
with electrospinning. In third method, two separate needles were used simultaneously for electorspinning
of PCL and chitosan and in forth method PCL electrospinning was done in first step then chitosan
nanofibers were formed in the surface of PCL scaffold. Characterization of obtained nanofibrers was
carried out according to appropriate methods. According to the results CS/PCL scaffolds had application
capability as ‘’smart labels’’ in the food packaging systems.
94
Engineering Algae to Produce Recombinant Biomolecules
A. Yıldırım*
Ege University, Department of Bioengineering, İzmir, Turkey
Microalgae are photosynthetic organisms which can easily be grown and scaled up in short periods and in
relatively inexpensive culture conditions. Most of them are edible and naturally rich in proteins, fatty acids
and pigments. Recombinant production of valuable compounds with microalgae is a growing field of
biotechnology. Since the first attempts of transformation with Chlamydomonas reinhardtii, a great
number of molecules including therapeutic proteins, monoclonal antibodies, DNA vaccines, hormones
and lipids have been produced with this green microalgae, and a number of other algal species as well.
As a recombinant production system, microalgae stand out with some of the cellular properties like easy
transformation of nuclear and chloroplast genomes and proper post-translational modifications of
recombinant products. Recently developed methods for gene transfer to both genomes allow to reach
high yields of expression levels, which make microalgae more attractive and economically viable. Biofuel
production from microalgae as a renewable energy source is one of the main research fields of algal
biotechnology, and engineering lipid metabolism aiming high level expression of cellular lipids is a
promising approach for the improvement of the final product. Edible vaccines from algae is another topic
reveals the advantage of algal systems especially over plant based productions mainly from the points of
culturing time, which may take months to years with plant systems, and the nonexistent risk of
contamination by pollen or by gene flow to the other crops. With the ability to produce even complex
proteins in a correctly folded forms, microalgae offer an effective system for the production of
therapeutics, pharmaceuticals and many other recombinant high value compounds.
95
Cryogels as Biomaterials
A. Kumar1, S. Egri2
1 Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur,
Kanpur-208016, UP, India, 2Gaziosmanpaşa University, Department of Bioengineeering, Tokat, Turkey.
Biomaterials have emerged as an important tool in cell and tissue engineering. It provides the matrix for
the development of tissue substitutes that can replace the diseased tissue or organ. Our work focuses in
developing the cryogels as biomaterials for various applications in cell and tissue engineering. These
cryogel biomaterials have been applied in technologically challenging processes like, tissue engineering,
cell separations, bioreactors for extracorporeal devices and therapeutic protein production. Here we have
applied cryogelation technology for the fabrication of biomaterial scaffolds for different biotechnological
and biomedical applications. The cryogel scaffolds were produced in freezing conditions from polymers
or polymeric precursors using crosslinking agents. After the gels were synthesized at sub-zero
temperatures, they were freeze thawed to generate the porous network. The scaffolds were thoroughly
characterized for physico-chemical properties and biocompatibility. In the preparative cell separation
process we have developed a generic affinity based monolithic chromatographic method for the
separation of human cord blood stem cells and other cell types. Other applications of these matrices have
been the cultivation of the mammalian cells on the macroporous support matrix for the production of
protein therapeutics and for the design of a bioartificial lever support system. We have also explored the
role of cryogel biomaterial for cartilage, bone, skin and neural tissue engineering applications and stem
cell differentiation. It plays an important role in different areas of biotechnology and biomedical
engineering like, regenerative medicine by restoring, maintaining or enhancing the tissue or organ
function. Thus cryogel biomaterials have shown promising applications in tissue engineering and
regenerative medicine and this study will give an overview on these potential areas.
96
Plasmonic Surfaces for Advanced Spectroscopy of Biological Specimens
A. Dana *
UNAM Institute of Materials Science and Nanotechnology, Bilkent University, Bilkent 06800 Ankara Turkey
Plasmonic metamaterials allow confinement of light to deep subwavelength dimensions, while allowing
for the tailoring of dispersion and electromagnetic mode density to enhance specific photonic properties.
For example, surface enhanced Raman scattering (SERS) benefits from the simultaneous presence of
plasmonic resonances at the excitation and scattering frequencies. By proper design of the plasmonic
band structure to satisfy this condition, highly repeatable and spatially uniform Raman enhancement is
demonstrated. It is shown that high spatial uniformity plasmonic enhancement can be used for super-
resolution Raman imaging, providing a label-free method with 20 nm far field optical resolution. An
optimization of the surfaces yield wide area super-absorber surfaces, with 90% absorption from 400-800
nm. The surfaces have an enhancement level of about 108, enabling the observation of single molecule
Raman signals using the camera of a mobile phone. Complementary to Raman scattering, infrared
absorption can also be enhanced by plasmonic surfaces, a method typically referred to as surface
enhanced IR absorption spectroscopy (SEIRA). Such improvement in IR absorption based sensing can be
achieved using metasurfaces with resonances in the infrared. We demonstrate metasurfaces that exhibit
multiple resonances spanning the visible and the infrared. Hierarchical plasmonic surfaces that
simultaneously enhance the infrared absorption and Raman scattering, allow observation of IR absorption
from monolayers as well as Raman scattering from single molecules.
97
Silver or Gold Deposited Magnetite Nanoparticles : Green Synthesis Approach with Plant Extract
A. Norouz Dizaji1, M. Yilmaz1 and E. Biskin1,2*
1Department of Chemical Engineering, Bioengineering Division, Hacettepe University, Ankara, Turkey
2Biyomedtek: Center for Bioengineering, Ankara, Turkey
In this study, the extract of Ligustrum vulgare plant was used as reducing and stabilizing agent for silver
or gold deposited magnetite nanoparticles. Firstly, magnetite nanoparticles (~6 nm) with
superparamagnetic properties, namely SPIONs were synthesized by co-precipitation method. The amount
of metal deposition can be manipulated by tuning reaction parameters such as AgNO3/ SPIONs or
HAuCl4/SPIONs ratio and amount of plant extract. UV-vis and Transmission Electron Microscope (TEM)
with energy dispersive X-ray (EDX) apparatus confirmed the metallic deposition. X-ray diffraction (XRD)
patterns depicted the presence of both metallic deposition and magnetic components as crystalline
structure. Magnetic saturation decreased when the amount of the metallic content increased that was
obtained via vibrating sample magnetometry (VSM). Fourier Transform Infrared (FTIR) spectra depicted
that functional groups such as carboxylic and ketone group originated from the plant extract that are most
probably responsible for the reduction and stabilization of Ag/Au carrying magnetite nanoparticles. The
proposed route was facile, viable and reproducible and metal deposited nanoparticles held remarkable
stability over long period time (~ 6 months) due to plant extract originated biomolecules.
98
Uni-directional Gold and Silver Nanorod Arrays as Surface Enhanced Raman Spectroscopy (SERS) Substrates
M. Yilmaz1,2, E. Biskin2,3 and G. Demirel1,3*
1Gazi University, Bio-inspired Materials Research Laboratory (BIMREL), Department of Chemistry, Ankara, Turkey.
2Hacettepe University, Department of Chemical Engineering, Bioengineering Division, Ankara, Turkey 3Biyomedtek: Center for Bioengineering, Ankara, Turkey
Herein, we demonstrated a simple and versatile concept for practical Surface Enhanced Raman
Spectroscopy (SERS) applications by combining 3-D anisotropic gold and silver nanorod arrays with
colloidal gold and silver nanoparticles having varying shapes. The gold and silver nanorod arrays having
different surface densities were fabricated on the surfaces via the angle deposition (OAD) technique
without using any template material or lithographic technique. Three morphologies of colloidal gold and
silver nanoparticles including sphere, rod, and cage were combined with anisotropic gold and silver
nanorod arrays to evaluate synergetic SERS enhancement investigations in our work. Additionally, we
demonstrated a proof of concept that indeed such synergetic enhancement in SERS signals may be utilized
effectively for the detection of some important biological and chemical toxins in trace amounts. Our
results suggest that the slightly tangled and closely-packed anisotropic gold nanorod arrays reinforced by
the nanoparticles may serve as an ideal SERS substrate to detect any analyte in trace amounts.
99
Synthesis of Ph-Sensitive Cholesterol Polymers and In Vitro Investigation of Interactions with Cell Membrane
V. Guven1, V. Bulmus1,2 *
1Izmir Institute of Technology, Biotechnology and Bioengineering Graduate Program, Urla, Izmir, Turkey 2Izmir Institute of Technology, Department of Chemical Engineering, Urla, Izmir, Turkey
The biomacromolecular therapeutics cannot penetrate the cellular membranes because of their polar and
macromolecular structures. Such therapeutics need delivery agents in order to reach cytosol or other
intracellular organelles at therapeutic concentrations. The aim of this study was to synthesize pH-sensitive
cholesterol containing polymers having varying compositions and molecular weights as potential
membrane-destabilizing agents for intracellular drug delivery applications and investigate interaction of
these polymers with cellular membranes. CMA was copolymerized with t-butyl methacrylate (t-BMA) via
RAFT polymerization to produce cholesterol containing copolymers following a procedure reported
previously. P(t-BMA-co-CMA) copolymers were hydrolyzed to poly(methacrylic acid-co-CMA) (P(MAA-co-
CMA) to obtain water soluble, pH-sensitive copolymers. The pH-responsive behavior of the copolymers
was demonstrated via UV−visible spectroscopy and dynamic light scattering measurements. These
measurements revealed that (P(MAA-co-CMA) copolymers having 2 or 4 mol% CMA and varying molecular
weights between 4 Kg/mol and 60Kg/mol form nanoparticles at pH 5.5 while the same copolymers exist
as unimers at pH 7.4. Copolymers having 8 mol% CMA and varying molecular weights form aggregates at
both pH values. The cell viability results (MTT assay) indicated that p(MAA-co-CMA) at 250 µg/ml
concentration are not cytotoxic to NIH3T3 cell line. Hemolysis assays revealed that P(MAA-co-CMA)
having a molecular weight above 20,000 g/mol did not show hemolytic activity regardless of CMA content.
Lower molecular weight copolymers having 4 mol% CMA showed hemolytic activity. Interestingly, the
fluorescence microscope investigation of NIH3T3 cells after incubation with fluorescent-labelled P(MAA-
co-CMA) having 2 mol% CMA and a Mn of 20000 g/mol showed the release of copolymer into cytosol.
100
Cytotoxic and Apoptotic Effect of Some Ferrocenoyl Furan Derivatives
on MCF-7 Cell Line
E. Arat1*, B. Uçar1, M. Türk1,2, A. Bulut2, M. Tombul2
1*Kırıkkale University, Scientific and Technologıcal Research Laboratories, Kırıkkale, Turkey 1,2Kırıkkale University, Faculty of Engineering, Department of Bioengineering, Kırıkkale, Turkey
2Kırıkkale University, Faculty of Art and Sciences, Department of Chemistry, Kırıkkale, Turkey
In this thesis, the syntheses of ferrocenoyl furan derivatives through Friedel-Craft acylation reaction
have been performed. Five original ferrocenoyl furan derivatives have been synthesized and their
structures have been characterized with spectroscopic methods (1H NMR, 13C NMR ve FT-IR).
Ethylaluminyumchloride, (EtAlCl2),as catalyst has been employed for the first time during the synthesis
of these compounds. When examining the yields of the synthesized products, catalyst was found to be
work well. Some of the ferrocenoyl furan kethone derivatives of cytotoxic, apoptotic and necrotic effect
against cancer cells determined by in vitro tests.
101
History of Nano-Scale Drug Delivery Systems
Allan S. Hoffman, ScD
University of Washington, Bioengineering Department, Seattle, WA 98195 USA
Nano-scale drug delivery systems (DDS) are very special. They are special because they may be targeted
to specific cells in specific tissues (eg, tumors) or organs, (eg, liver). The size scale of these NanoDDS
ranges from a few nm up to several hundreds of nm. The nanocarrier may be conjugated to a drug, (eg,
PEGylated drugs) or it may be complexed ionically to a drug of the opposite charge, (eg polyplexes and
lipoplexes) or it may physically entrap a drug (eg, liposomes). This has led to many different types of
NanoDDS, such as liposomes, polymer-drug conjugates, PEGylated drugs, polymeric micelles, polycation-
nucleic acid drug complexes such as polyplexes and lipoplexes, albumin-drug complexes, nano-scale
particles, dendrimers and polymersomes. It may also be biologically (“actively”) targeted to specific cells
using monoclonal antibodies or small molecule ligands, or physically (“passively”) targeted to tumors via
leaky blood vessels (EPR effect). The molecular weight (or size) and biodegradability of the nanocarrier
are both very important to its eventual clearance from the body after delivering the drug. In recent years,
the number of FDA-approved NDDS has grown significantly. Most of the approved NanoDD formulations
have been applied to treating cancer. This talk reviews the origins and evolution of this very special and
important sub-field of controlled drug delivery.
102
Ag and Al2O3 Nanoparticles Long and Short Term Impacts on Waste Activated Sludge Anaerobic Digestion
E.Kökdemir1, A.Perendeci1,*
1Akdeniz University, Faculty of Engineering, Department of Environmental Engineering, Antalya, Turkey
Due to their unique properties and changeable atomic packing, nanoparticles (NPs) are quite favorable for industrial use and therefore require an extensive research in many scientific fields. NPs are involved in many biomedical areas such as dental treatment, drug delivery and surgery materials by virtue of their different properties. These NPs are mainly cerium oxide (CeO2), silver (Ag) and iron (III) oxide (Fe2O3) with their cell protector or anti-bacterial characteristics. In addition to above mentioned more need-specific industrial products, products with very high production rates such as daily cleaning products, cosmetics, food packaging, many different coatings and paints contain a great amount of NPs such as titanium dioxide (TiO2) and aluminum oxide (Al2O3) as well. Anaerobic digestion is one of the most optimum and widely used stabilization methods for waste activated sludge. Due to the many microorganism groups involved in anaerobic digestion, the process is sensitive to the environmental conditions such as novel chemicals. Nanoparticles can be categorized as a novel chemical because there are many unknowns about their interactions with their environment. In order to understand these unknowns, many studies on the impacts of nanoparticles on aerobic microorganisms were conducted. On the other hand only little is known about the impacts of nanoparticles on anaerobic microorganisms. In this study, Ag and Al2O3 nanoparticles (NP) were chosen due to their extensive use in medical and commercial products and their high potential of getting in contact with water. 5, 50, 150, 250 and 500 mgNP/gTS concentrations of NPs were added to waste activated sludge to evaluate the long term effects of NP’s on waste activated sludge anaerobic digestion by means of biochemical methane potential (BMP) test. In order to determine the acute affects of nanoparticles on waste activated sludge anaerobic digestion, ISO 13641-1 inhibition test was performed. During the inhibition test, 750 and 1000 mgNP/gTS concentrations were used in addition to the same NP concentrations which were used in the BMP test. According to the results of approximately 50 days long BMP test, the cumulative increase of BMP values of 250 mgAg/gTS Ag NP concentrations has been determined as 7.9% relatively to the control group, while 500 mgAg/gTS concentrations display maximum 12.1% decrease. Al2O3 NPs caused a positive catalyst impact on biogas production at a rate of 14.8% for 250 mgAl2O3/gTS concentration and no inhibition impact was observed during the test. Within the 72 hours long ISO 13641-1 inhibition analysis, inhibition has been determined through total gas pressure measurement unlike the methane production measurement in BMP tests. According to the results of ISO 13641-1 test, neither Ag nor Al2O3 NP caused a significant inhibition effect on the biogas production from municipal waste activated sludge anaerobic digestion. Distinctively from BMP tests, NPs didn’t cause significant impacts on biogas productions in acute conditions which may be interpreted as exposure time is an important parameter on the evaluation of NP toxicity on anaerobic microorganisms as well as concentration.
103
Auricular Cartilage Using of Gold Nanorods As a Drug Carrier For Enhanced Delivery of Gentamicin to Staphylococcal Infection Foci
A. Ahangari1, M. Salouti2*, Z. Heidari2
1Islamic Azad University, Young Researchers Club, Hidaj Branch, Hidaj, Iran. 2Islamic Azad University, Biology Research Center, Zanjan Branch, Zanjan, Iran.
The widespread problem of antibiotic resistance in pathogens such as Staphylococcus aureus has
prompted the researchers for innovating new antimicrobial approaches. Although many methods for
diagnosing and treating of infectious diseases currently exist, there is an urgent need for new and
improved approaches for bacterial destruction. It is now clear that a nanotechnology-driven approach
using nanoparticles to selectively target and destroy pathogenic bacteria can be successfully
implemented. The present study focuses on the conjugation of gentamicin molecules with gold nanorods
via the Nanothink acid as a linker and its application in delivery of gentamicin to infection foci due to
Staphylococcus aureus. The interaction between gentamicin and gold nanorods was confirmed by FT-IR
spectroscopy. The high performance liquid chromatography (HPLC) and atomic absorption spectroscopy
analyses showed that 2050 gentamicin molecules were attached to each gold nanorod. Minimum
inhibitory concentration and minimum bactericidal concentration studies showed the enhanced
antibacterial effect of gentamicin-gold nanorods complex in comparison with free gentamicin. The
biodistribution study demonstrated localization of the complex at the site of Staphylococcal infection with
high sensitivity in mouse model. our findings indicated that gold nanorods conjugated antibiotics are more
efficient and might have significant therapeutic implications.
104
Cargo Transportation in Droplet Based Microfluidic Systems Having Anisotropic and Unidirectional Nanostructures
B. Ozdemir1*, E. Babur1, H. Erdogan1, G. Demirel1
1Gazi University, Department of Chemistry, Bio-inspired Materials Research Laboratory, Ankara, Turkey
Throughout the millions of years of evolutions, living beings has attuned with the environmental
conditions by means of their gained adaptations. These adaptations are seen on regular architectural
dimensions in the organism such as lotus leaf, butterfly wings and water strider legs. For instance, lotus
leaf can clean itself with the help of its nanostructures on its pad and display a superhydrophobic feature.
This situation is encountered with a different aspect on a butterfly’s wing. On butterfly wing, a directional
patterns exists along with the nano architecture. Thus, butterfly wards off the dirt from its body while
flapping. By imitating these features from nature, different applications have been realized. In this study,
surfaces with anisotropic and directional features are examined in terms of the ability to control the
droplet movements in digital microfluidic systems. In the study where synthetic anisotropic surfaces have
been prepared with the oblique angle polymerization method, dichloro-[2,2]-paracyclophane molecules
are used as initial molecules and the unidirectional polymeric nanostructures are amplified on different
surfaces with the vacuum based oblique angle polymerization method. Wetting behaviors of the prepared
surfaces were investigated by water contact angle measurements and their morphological
characterizations were done with electron microscope. Additionally, directional droplet movement
studies have been conducted on the prepared surfaces. It has been observed that water droplets can
move on the direction of nanostructures’ growing, but hang on in the opposite direction. To apply this
phenomenon on microcargo carrying, surfaces are covered with anisotropic synthetic nanostructures and
water droplets are moved in the intended direction by giving vibrations.
105
Fabrication of Graphene Loaded Porous PLLA/PCL Structures for Bone Tissue Engineering
E.Tekay1, Z.B. Ahi1, Z. Ustundag2, H.M. Aydin3, K.Tuzlakoglu1*
1Yalova University, Department of Polymer Engineering, Yalova, Turkey
2Dumlupinar University, Chemistry Department, Kutahya, Turkey 3Hacettepe University, Department of Environmental Engineering, Ankara, Türkiye
Carbon- based nanomaterials, especially graphene and its derivates, have gained much attention the use
in tissue engineering applications due to their excellent chemical, electrical and mechanical properties.
Besides the exclusive properties such as easy surface functionalization, maximum surface/volume ratio,
graphene has also showed the positive influence on the mesenchymal stem cell differentiation. In the
present study, we aimed to prepare highly porous biodegradable scaffolds made of PLLA/PCL blend
composed with graphene oxide. Supercritical CO2 method was used to obtain interconnective porous
structure, following salt leaching technique. SEM analysis was use to visualize pore structure and GO
distribution. Well integration of GO into polymeric phase was also confirmed by XRD analysis. The
crystallinity of both PLLA and PCL were decreased in the presence of GO. GO addition also had a positive
influence on compressive strength of the scaffolds, having a compression modulus 0.264MPa and
0.473MPa for unloaded scaffold and 10% GO loaded scaffold, respectively. Thus, the cellular response
studies to these graphene-based constructs are ongoing to prove the success of produced scaffold.
106
Vapor-Phase Deposition of Polymers As A Simple And Versatile Technique To Generate Paper-Based Microfluidic Platforms For Bioassay Applications
E. Babur1*, B. Ozdemir1, H. Erdogan1, G. Demirel1
1Gazi University, Bio-inspired Materials Research Laboratory, Department of Chemistry, Ankara, Turkey
Paper-based microfluidic platforms arouse an increasing interest in clinic diagnosis, food quality-control
processes and environmental monitoring procedures owing to their easy usage, low costs and ability to
provide qualitative and quantitative analysis. Considering most of the diagnosis and prognosis systems
are expensive, time taking, and necessitating expert usage, one can foresee that paper based fast
diagnosis platforms will constitute great importance in terms of both production and usage ease. Despite
the fact that a series of innovative techniques have been realized recently, cost-effective and
multidimensional new strategies are needed to be developed to reach their full potential. In this study,
with the aim of producing paper based microfluidic platforms in the intended form, one-step vapor phase
polymerization of dichloro-[2,2]-paracyclophane method has been utilized. For this purpose, monomer
has been vaporized in a sublimator which is placed in a polymerization system working under vacuum.
Afterwards, it has been transformed into active radicalic monomers by disintegrating with high
temperature in pyrolizer and transmitted to vacuum circle. By sticking it to paper sample with the help of
a magnet, metal mask-prepared beforehand in the required format has been placed in the vacuum circle.
With the beginning of polymerization of active radicalic monomers on paper surface they contacted,
patterned paper which will be used as analysis platform has been produced. Additionally, in the already
produced platforms, analyses of certain target molecules such as glucose, protein, ALP, ALT and uric acid
are displayed. Observation limit for each target molecule has been determined, and found out to be 25
mg/dL for glucose, 1.04 g/L for protein, 7.81 U/L for ALP, 1.6nmol/L for ALT and 0.13mmol/L for uric acid.
107
The New System for Protein Transport and Release: Stimuli Responsive Lipid Nanotubes
H. Unsal1, N. Aydogan1,*
1 Hacettepe University, Department of Chemical Engineering, Ankara, Turkey
Lipid nanotubes have lots of advantages making them preferential for a wide variety of applications. Due
to their high biocompatibility, simple production and high inner volume, one of the most common
application areas for lipid nanotubes is transport and controlled release of drugs, proteins,
biomacromolecules, etc. In this study, hemoglobin (Hb) and BSA are loaded to the new Aqua (AQ-NH-
(CH2)10COOH) nanotubes and the loading capacities and release profiles of these model proteins are
investigated. With the help of the tubular geometry as well as the special functional groups existing on
the inner and outer nanotube surfaces, the loading capacities of nanotubes for the studied model proteins
are quite high comparing with the other systems in the literature. Additionally, Aqua nanotubes achieve
high loading capacities with smaller diameters which is another important advantage for biomedical
applications since it allows the passage of drug-laden nanotubes from the various barriers in the body.
Specially designed Aqua nanotubes have a dual stimuli-responsive character and nanotube morphology
and charge properties can be controlled by pH and redox effects. These properties of Aqua nanotubes
allows controlling the guest-host interactions with external triggers. It has been found that the loading
capacities of the nanotubes change with solution pH and temperature. Also, the released amounts
strongly depend on the solution pH making it possible to selectively release the proteins by the pH change.
Aqua nanotubes can release a high portion of the BSA loaded and only a little portion of Hb. These results
are promising as regards of the potential usage of Aqua nanotubes for both the controlled release and
artificial blood applications.
108
Plasma Treated Biomaterial Surfaces
Hilal Turkoglu Sasmazel *1
1Atilim University, Department of Metallurgical and Materials Engineering, Ankara, Turkey
Recently, nanoscale investigations in various scientific fields indicate the importance of nanostructures
(nanoparticles, nanopatterns, nanotopographies, nanocomposites) for advanced material properties and
for extending these properties beyond typical material properties. Biomolecule immobilization and tissue
engineering, advanced materials (superhydrophilic, superhydrophobic, etc.,), organic material devices,
miniaturization in the electronics industry, all require nanotopographies. The interactions between the
implant and biological system on the micrometer and nanometer scale, and the physicochemical surface
properties of the materials, for example, chemical composition, wettability, surface energy,
semiconductor properties and surface charge, play an important role for the biocompatibility of a
material. Plasma exposure of surfaces can produce nanostructured materials on metals, semiconducting
layers or macromolecular compounds. It is possible to change the chemical composition and properties
such as wettability, metal adhesion, dyeability, refractive index, hardness, chemical inertness, lubricity,
and biocompatibility of materials surfaces. Therefore plasma processing is of growing interest in the field
of biomedical engineering. The application of plasma-based techniques is quite diverse, and examples of
applications include cleaning/sterilization, coating or depositing, and implantation modification of surface
chemistry of a substrate. Some representative examples/applications of the plasma treatments (low
pressure and atmospheric pressure plasmas) in biomaterials will be given in this talk. Studies carried out
by Sasmazel’s research group with the synthetic and natural, biodegradable and nonbiodegradable
polymeric surfaces by low pressure and atmospheric pressure (Dielectric barrier discharge and Nozzle
type) will be mentioned briefly.
109
A Comparison of the Virulence & Antibiotic-Resistance Profiles of Escherichia Coli O157 Recovered from Freshwater Epilithic Biofilms, Agricultural Animal Populations, and From
Incidents of Clinical Disease in the UK
I. Cooper1, J. Caplin2*
1University of Brighton, School of Pharmacy & Biomolecular Sciences, Brighton, BN2 3EQ, UK 2University of Brighton, School of Environment & Technology, Brighton, BN2 3EQ, UK
This project investigated the clonal relationships between E. coli O157 isolates recovered from pooled
animal faeces, river sediment and from cases of clinical disease in humans in an attempt to establish
whether a link exists between animal- and environmental isolates, and those known to cause human
disease, and to investigate their virulence and antibiotic resistance profiles. PCR revealed that the most
prevalent virulence factor amongst the animal- & sediment-associated isolates was the stx2 gene, whilst
amongst the clinical isolates; the most prevalent virulence factor was the intimin gene. The most frequent
combinations of virulence factors were stx1 + hly + eaeA amongst the animal-associated isolates, and stx2
+ hly amongst the clinical isolates. Amongst the clinical isolates, the most frequently recovered resistance
profile was the combination of resistance to amoxy/clav and neomycin plus β-lactamase production;
whilst amongst the sediment and animal-associated isolates, resistance to amoxy/clav plus β-lactamase
production were the most frequently recovered resistance profiles. Mathematical cluster analysis based
on RAPD typing revealed that distinct clusters existed within each of the animal, sediment and clinical
populations, respectively. However, whilst there was significant clustering between the sediment- and
animal-associated E. coli O157 isolates, the clinical E. coli O157 isolates did not cluster with isolates from
other sources. This could suggest that the clinical E. coli O157 isolates represent a group that is genetically
distinct from those recovered from animal and sediment habitats, and that several distinct populations of
E. coli O157 exist within the natural environment.
110
Impact of Plasmid Downstream Processing on Transient Transfection
J. de la Vega1*, G. Monteiro1, D. M. Prazeres1
1Universidade de Lisboa, IBB – Institute for Biotechnology and Bioenginereing, Instituto Superior Técnico, Lısbon, Portugal
The ability of plasmids to transfer genes into eukaryotic cells can be explored to treat diseases, immunize
against infectious agents and produce recombinant proteins. This purpose calls for an understanding of
the aspects that influence plasmid delivery. This work analyzes the effect of purification, host-cell
impurities and DNA stabilizers on the efficiency of plasmid-mediated cell transfection. A plasmid harboring
a green fluorescence protein gene, LipofectamineTM-based liposomes and Chinese Hamster Ovary cells
were used as models. Results demonstrate that quality attributes of preparations (e.g. impurities, degree
of plasmid compaction) depend on the purification methodologies and affect the size, charge and stability
of lipoplexes prepared thereof. This significantly affected transfection and expression of the GFP gene.
Plasmid solutions were spiked with known amounts of protein, RNA and gDNA (5-100% w/w). Nucleic acid
impurities had a dramatic impact in transfection and cell viability even at low concentrations. The addition
of DNA stabilizers (cellobiose, trehalose and DNAstable plus TM) was found to increase shelf-life stability
of plasmid preparations kept at room temperature (~100% transfection activity after 1 year with
DNAstable plus TM) and prolong gene expression after transfection when compared with control samples.
111
NF-kB Signaling in Cancer Therapy
K. Ozturk1*, E. Oksuzoglu1
1Aksaray University, Faculty of Science and Art, Department of Biology, Aksaray, Turkey
Transcription factor nuclear factor kappa B (NF-kB) has been recently connected with multiple aspects of
tumorogenesis, including the control of tumor cell proliferation, migration, angiogenesis, cell cycle
progression, and inhibition of apoptosis. Indeed, NF-kB is constitutively activated in several types of
cancer cells and it is generally regarded as an anti-apoptotic and pro-oncogenic signal. In addition,
activation of NF-kB in cancer cells by chemotherapy or radiation therapy is often associated with
acquisition of resistance to apoptosis. This has emerged as a significant impediment to effective cancer
treatment. In combination with chemotherapy, inhibitors of the NF-kB pathway such as proteoseme
inhibitors are used with success as treatment against cancer. In contrast to the negative effects of NF-kB
activation, recent reports suggest that in certain situations NF-kB can promote apoptosis and may be
viewed as a tumor suppressor gene. This opposite two function of NF-kB activation depends on cell type
and stage, the stimulus, and the context of avtivation. The dual activity of NF-kB complicates the systemic
use of broad spectrum NF-kB inhibitors for treatment of cancer and it has been suggested to design better
therapeutics that spesifically unleash the pro-apoptotic activity of NF-kB.
112
Blood Flow and Interface Interaction with Medical Assisting Devices
Khosrow Mottaghy1*
1RWTH Aachen University, Institute of Physiology, Aachen, Germany
Medical devices are used as implants or even as a total replacement of a natural organ. They can be
integrated and also applied extracorporeal in order to support at least partially the sever diseased organ
often also as bridging to transplantation. An extracorporeal circulation itself consists of a large variety of
applied biomaterials with different geometries and their own blood flow characteristics. There is a big
necessity for supporting the internal organs e.g. in cardio-pulmonary bypass in heart surgery or dialyzers
for therapy of chronic kidney insufficiency, and also new approaches for extracorporeal liver support. Long
term support of sever diseased internal organs enhance even more the challenge to maintain the
physiological properties of blood and avoiding or at least reducing drastically its trauma. The coagulatory
response of the blood is, however, in tight connection to the fluid dynamic characteristics of blood flow.
Here are especial designed in-vitro model studies introduced with some experimental studies in order to
investigate the effect of red blood cell distribution in the shear field as well as the aggregation behavior
of platelets. Moreover, proposals are introduced in order to discriminate the effect of “contact time” of
blood at the interface of the biomaterials, combined shear stress and secondary flows affecting e.g. the
growth rate of platelet aggregation and red blood cells trauma. The examples should demonstrate the
effect of blood flow conditions in connection to the specific biomaterial properties used in the system.
Furthermore, examples are given for haemocompatibility improvement by different surface modification
methods and its testing criteria including specific testing designs for a more realistic transformation to a
possible clinical application.
113
Preparation and Characterization of Magnetic PHEMAH Nanoparticles for Protein C
Purification
D. Cimen1*, N. Bereli1, A. Denizli1
1Hacettepe University, Department of Chemistry, Ankara, Turkey
Protein C (PC) is the pivotal anticoagulant and antithrombotic in the human coagulation cascade. Protein
C is showed its anticoagulant effect with Protein S (PS) by inactivating FVa and FVIIIa. PC is at a
concentration of 4 µg/mL in human blood. In the absence of Protein C (Protein C deficiency) increases risk
of generation thrombosis. When these blood clots break away from the surface of the vein and enter the
blood stream, they will induce strokes, heart attacks and pulmonary embolisms. Blood clotting can be life
threatening if it is not recognized early and treated. Heparin and coumadin are commonly used to the
treatment for protein C deficient patients. However, these therapeutics have dangerous side effects as
excessive bleeding, stroke, organ failure. In contrast, protein C has no known side effects; therefore,
therapeutic replacement of protein C appears very promising. Immobilized metal ion affinity
chromatography (IMAC) is well known as a powerful technique for the purification of proteins possessing
exposed electrodonating aminoacid residues on their surfaces such as the imidazole group of histidine,
thiol group of cysteine and indoyl group of trytophan. Many transition metals can form stable complexes
with electron-rich compounds and may coordinate molecules containing O, N and S by ion dipole
interactions. IMAC introduces an interesting approach for selectively interacting biomolecules on the basis
of their affinities for metal ions. The separation is based on the interaction of a Lewis acid (electron pair
acceptor), i.e., a chelated metal ion, with an electron donor atoms (N, O and S) on the surface of the
protein. Proteins are assumed to bind mainly through the imidazole group of histidine, to a lesser extent,
the indoyl group of tryptophan and the thiol group of cysteine. Co-operation between neighboring
aminoacid side chains and local conformations play important roles in protein binding. The low cost of
metals and the reuse of materials without any loss of metal-chelating properties are the attractive
properties of metal affinity separation .In this study, poly(hydroxyethyl methacrylate-N-methacryloyl-(L)-
histidine methyl ester) [PHEMAH] nanoparticles were prepared by mini-emulsion polymerization. N-
Methacryloyl-(L)-histidine methyl ester (MAH) was used as the metal-chelating ligand. The obtained
nanoparticles were characterized with Fourier transform infrared spectroscopy (FTIR-ATR), zeta-size
analysis, scanning electron microscopy (SEM) and electron spin resonance (ESR) spectroscopy.
114
New Drug Targets for Metastatic Breast Cancer
Ayse Kevser Özden1*
1Hacettepe University, Faculty of Medicine, Department of Medical Biochemistry, Ankara, Turkey
Breast cancer is the most frequent type of cancer in women and it ranks as second common type of cancer
following lung cancer. Cancer cells gain malignant character and continous proliferative capacity and
immortality due to several genetic and epigenetic anomalies that they display. Especially, overexpression
of certain receptors, mutations in signal pathway components such as PI3K/Akt/mTOR, ERK/MAPK are
frequently detected in breast cancer. The aberrant expression of PI3K/Akt/mTOR and Notch signaling
pathways as well as expression of nNav 1.5, the neonatal form of sodium chanel is implicated in malignant
transformation and metastasis of breast cancer cells. The metastatic breast cancer cell lline, MDA-MB-
231 is used to analyse the effects of nNav1.5 and Noç-4 on mTOR, which is the central component of
PI3K/Akt/mTOR signal pathway and the effects of their inhibition on the proferative and metastatic
properties. The proliferation is detected by WST and expressions were analysed by PCR and Western blot.
Zymography and wound healing assays were performed to detect some metastatic properties. It is found
that these signalling systems are connected and their inhibition decreases the metastatic potential. It is
concluded that, since signal systems form a web, it is important to understand their relations and Notch
signal system and Nav 1.5 sodium chanels are potential targets for breast cancer.
115
Comparison of Linear and Comb-Type PEG: In Vitro Interactions with Cells
I. Ozer1*, V. Bulmus1,2*
1Izmir Institute of Technology, Biotechnology and Bioengineering Graduate Program, Izmir, Turkey
2Izmir Institute of Technology, , Department of Chemical Engineering, Izmir, Turkey
PEGylation has become one of the most widely used technologies in pharmaceutical industry not only for
the modification of biomolecules but also for the surface improvement of liposomes and nanoparticles.
The molecular architecture of PEG affects the pharmacokinetic properties of biomolecules/nanoparticles
it is attached to. Comb-type PEGs are one of the emerging architectures that consist of poly (meth)acrylate
backbone and a number of linear oligoethylene glycol chains grafted to the backbone. The aim of this
study is to investigate interactions of comb-type PEG with in vitro cultured cells and compare to linear
PEG counterparts. For this purpose, PEG-methacrylate polymers (p(PEG-MA)) at different molecular
weights (10 and 20 Kg/mol) were synthesized via RAFT polymerization. The effects of polymers on
cancerogenic A549 and healthy BEAS-2B human lung cell lines were investigated. MTT assay showed that
p(PEG-MA) and linear PEG decreased the cell viability in a dose-dependent manner. However, the lowest
cell viability was above 50% indicating no significant cytotoxic effect of both types of polymers. Cellular
uptake of both types of polymers completely diminished at 4oC suggesting energy-dependent
internalization mechanism of both types of polymers. Comb-type polymers were found to be taken up
more by A549 cells. Comb-type polymers were internalized by A549 cells mainly via actin-dependent
pathway, while linear PEGs were internalized by A549 cells via actin and also microtubule-dependent
pathways depending on their molecular weight. BEAS-2B cells took up all polymers via microtubule-
dependent pathway.
116
Genetic manipulations of bacteria
Y. Ulusu 2, S. B. Şentürk 3, H. Kuduğ 1, İ. Gökçe 1
1Gaziosmanpaşa University, Faculty of Engineering, Dept. of Bioengineering, Tokat, Turkey 2Karamanoğlu Mehmetbey University, Faculty of Engineering, Dept. of Bioengineering, Karaman, Turkey
3Gaziosmanpaşa University, Faculty of Science, Dept. of Chemistry, Tokat, Turkey
Genetic engineering, also genetic manipulation of a bacterium is the direct manipulation of an organism's
genome using biotechnology, implies that the DNA content of the bacterium is changed in a deliberate
manner. New DNA may be inserted into the genome of the host organism by first isolating and copying
the genetic material of interest using molecular cloning methods to generate a DNA fragment, or by
synthesizing the DNA, and then inserting this construct into the host organism. Genes may be removed,
or "knocked out", using a nucleases. Gene targeting and its engineering is a technique that uses
homologous recombination to change an endogenous gene, and can be used to delete or add a gene, or
introduce point mutations in the interested part of the bacterial genome. E. coli bacterium was the first
organism to be genetically modified. Plasmid DNA containing new desired genes can be inserted into the
bacterial cell and the bacteria will then express those genes. These genes can code for medicines or
enzymes that process food and other biochemical substrates. By adding a gene to a bacterium we can
provide the bacterium with new capabilities, for example with a new enzymatic activity such as antibiotic
resistance. By inactivating a gene in a bacterium, we can study both the function of the gene product, and
if the gene encodes an enzyme, the function of the metabolic pathway the enzyme is part of. We use E.
coli as a recombinant protein factory for production of molecular and industrial enzymes. We are also able
to colour the bacterium using Green Fluorescent Protein, (GFP) or its variants (different coloured by using
point mutations on the GFP gene) to express it or fuse GFP to the desired gene to control and visualize
the bacterium while studying the pathway or gene products in our lab. A number of bacteria are also of
particular interest for genetic manipulation. They include plants pathogens Agrobacterium rhizogenes and
A. tumafaciens for special importance for the genetic manipulation of plants and photosynthetic bacteria
such as Cyanobacteria for studying photosynthesis and nitrogen fixation. There are too many E. coli strains
that tailored for the desired modifications. Almost the same considerations for host design in E. coli apply
to some other bacteria and especially B. subtilis probably offers the best range of host strains in the other
bacteria.
117
Functional Optical Brain Imager (fNIR): A Case Study in Commercialization of Academic Innovation
Banu Onaral1*
1Drexel University, School of Biomedical Engineering, Science and Health Systems, Philadelphia, PA, USA
Near-infrared spectroscopy (NIRS) based optical imaging systems have been widely used in functional
brain studies as a noninvasive tool to study changes in the concentration of oxygenated hemoglobin (oxy-
Hb) and deoxygenated hemoglobin (deoxy-Hb). Based on the NIRS technique, Drexel University’s Optical
Brain Imaging team has developed a functional brain monitoring system (fNIR) to assess cognitive activity
of healthy subjects and patients. The fNIR is a portable, safe, affordable and negligibly intrusive monitoring
system which enables the study of cortical activation-related hemodynamic changes under various field
conditions. This presentation will provide an overview of applications of the fNIR including human
performance assessment, learning and training, depth of anesthesia monitoring, neuro-rehabilitation,
brain computer interface for locked-in patients, mental health applications as well as ‘brain-in-the loop’
applications in motor learning and robotic rehabilitation. The audience will be introduced to the Coulter
Translational Research Partnership Model for translation and commercialization of academic innovations
tat address an unmet need in health care and to the Cognitive Neuroengineering and Quantitative
Experimental Research (CONQUER) CollabOrative which hosts the Optical Brain Imaging team and
welcomes all regional, national and international partners dedicated to the research, development,
integration, translation, productization, field deployment and commercialization of functional imaging
techniques to monitor human brain activation in natural environments.
118
The Origins and Evolution of Controlled Drug Delivery Systems
Allan S. Hoffman1*
1University of Washington, Bioengineering Department, Seattle, WA 98195 USA
In this lecture I will present a short history of the controlled drug delivery field. This exciting and active
field is quite young, and really began only around 50 years ago. The earliest controlled drug delivery
devices to reach the clinic were macroscopic in size, and were implanted sub-cutaneously, applied
topically on the skin, inserted into or onto mucosal regions of the body, or ingested as tablets. These
devices were designed to provide “zero order” controlled drug delivery. The next important DDS to reach
the clinic were injected sub-cutaneously; they were based on degradable polymers in the form of drug-
loaded microparticles or phase-separating polymeric masses. These “depot” DDS provided “sustained”
release at a specific site in the body. More recently, many diverse nano-scale DDS have been developed
and are being introduced into the clinic. They include PEGylated drugs, polymer-drug conjugates and
complexes, PEGylated polymeric micelles, liposomes, nanoparticles, dendrimers and others. These
interesting nano-scale DDS are usually long-circulating, and may be actively or passively targeted to
specific cells or tissues in the body. Design of drug nanocarriers is currently the most active and exciting
area of development in the field of controlled DDS.
119
Gelatin-Hydroxyapatite Cryogels with Bone Morphogenetic Protein-2 and Transforming
Growth Factor Beta-1 for Calvarial Defects
I. Inci1, S. Odabas2, I. Vargel*3, E. Guzel3, P. Korkusuz4, T. Cavusoglu5, H. Kirsebom6, H. H. Celik7, F.
Demirkazik8, B. Mattiasson7, E. Piskin*1
1 Hacettepe University, Chemical Engineering Department and Bioengineering Division- Center for Bioengineering
and Biyomedtek, Beytepe, Ankara, Turkey 2Ankara University, Chemistry Department, Biochemistry Division, Ankara Turkey
3Hacettepe University, Plastic& Aesthetic Surgery Department, Faculty of Medicine, Ankara, Turkey 4Istanbul University, Histology & Embryology Department, Cerrahpasa Faculty of Medicine, Istanbul, Turkey
5Hacettepe University, Histology & Embryology Department, Faculty of Medicine, Ankara, Turkey 6Memorial Hospital, Plastic& Aesthetic Surgery Department, Ankara, Turkey
7Lund University, Department of Biotechnology, Center for Chemistry and Chemical Engineering, Lund, Sweden 8Hacettepe University, Anatomy Department, Faculty of Medicine, Ankara, Turkey 9Hacettepe University, Radiology Department, Faculty of Medicine, Ankara, Turkey
Over recent years, several tissue engineering techniques are used for bone regeneration. In this study
gelatin-hydroxyapatite (Gelatin-HA) cryogel scaffolds were used with/without bone morphogenetic
protein-2 (BMP-2) and transforming growth factor beta-1 (TGF-β1) to heal critical sized bone defects.
Releases of growth factors from the cryogels were performed up to 28 days in vitro. Moreover, in vivo
studies were performed in 6 groups and results were evaluated by micro computerized tomography (µ-
CT) and histology on 2 months and 4 months after surgery. Gene expression studies were also performed
on 2 weeks and 4 weeks after surgery. Collagen type I (Col I), alkaline phosphatase (ALP) and osteocalcin
(OSC) gene expression levels were analyzed. According to histology and µ-CT results, there was a
significant bone healing in the BMP-2 containing gelatin-HA cryogel group as compared to other groups
except autograft applied group. Moreover, significant increases were observed for Col I, ALP and OSC in
BMP-2 containing gelatin-HA cryogel group similar as autograft. However there was no significant increase
in the group of BMP-2 and TGF-β1 applied together. The results reveal that combination of gelatin-HA
cryogels with BMP-2 is a promising candidate for healing in critical sized craniofacial bone defects.
120
Tissue Engineering Scaffolds Made of Biodegradable Cryogels
Nimet Bölgen1*
1Mersin University, Faculty of Engineering, Department of Chemical Engineering, Mersin, Turkey
In recent years, hydrogels have been investigated and even marketed as biomaterials for diverse
applications. Cryogels are gel matrices that are produced in moderately frozen solutions of monomeric or
polymeric precursors. Cryogelation is an alternative rather new scaffold production method and the three
dimensional cryogel scaffolds prepared by using that technique have interconnected macroporosity and
excellent mechanical properties including flexibility and elasticity in their swollen form. Non-degrading
cryogels were synthesized previously from different type of polymers for chromatographic applications in
biotechnology. In this study, biodegradable cryogels based on biodegradable polymers were prepared to
create a potential application area for them in regeneration of tissues as scaffolds. The evaluation results
of the interaction of biodegradable cryogels with bone cells at different regimes in bioreactors for the
restoration of bone tissue and with articular chondrocytes for cartilage tissue engineering; the drug
releasing capacity; biocompatibility; combination capability with stem cells and tissue regeneration
performance of these cryogels will be summarized in this presentation.
121
Nanoparticle Mediated Antenna Type Radio-frequency Based Hyperthermia in Cell Cultures
B. Nasseri1, M. Yilmaz1, M.Turk2, I. C. Kocum3, E. Piskin1,*
1Hacettepe University, Chemical Engineering Department and Bioengineering Division, Centre for Bioengineering
and Biyomedtek/ Nanobiyomedtek, Beytepe, 06800, Ankara, Turkey 2Kirikkale University, Department of Bioengineering, Kirikkale, Turkey
3Baskent University, Department of Biomedical Engineering, Ankara, Turkey
Radiofrequency wave modality hyperthermia as non-invasive/non-destructive cancer treatment has
emerged a novel approach to eliminate drawbacks of traditional cancer therapy techniques such as
chemotherapy and radiotherapy. In this study, SPIONs, Au@SPIONs, AuNPs and AuNRs were synthesized
in proper morphologies and sizes according appropriate techniques. Synthesized nanoparticles were
induced by RF exposures in the next stages. For the first time, antenna modulus RF generator (200W
power/144.015MHz) as energy source has been designed and used in this study. Hyperthermic
temperature arise was followed during in vitro experiments on MCF-7 and L-929 cell lines which were
used along in-vitro experiments. MCF-7 cells were opposed marked apoptotic/necrotic cell death in the
presence of nanoparticles and RF exposures while L-929 cells were followed by less apoptosis/necrosis
indexes at the same conditions. Cells viability was followed under fluorescence microscopy after staining
by fluorescence dyes and cell viability indexes were evaluated then. According results, the highest
temperature arise was obtained in 30 ppm during cell-free experiments. Likewise, through in vitro
experiments the highest cell death was obtained by MCF-7 cells at 30 ppm and 180W RF power. L-929
cells were exhibited more viability values compared with MCF-7 cells. Nanoparticles nature, RF power as
well as cells type are main factors which affected apoptosis and necrosis indexes.
122
Conduits and Membranes Made Of Electrospun Gelatin
Özlem Eğri1, Deling Kong2, Erhan Pişkin3*
1Gaziosmanpasa University, Faculty of Engineering and Natural Sciences, Department of Bioeng., Tokat, Turkey 2Nankai University, Department of Life Sciences, The Key Laboratory of Bioactive Materials, Tianjin, China
3Hacettepe University, Chemical Engineering Department and Bioengineering Division, Centre for Bioengineering and Biyomedtek/ Nanobiyomedtek, Beytepe, 06800, Ankara, Turkey
We aimed producing conduits and membranes of gelatin, denatured form of collagen in order to provide
natural biomaterial for vascular and dermal applications. For this purpose, collagen from bovine source
was dissolved in Hexafluoroisopropanol with different concentrations varying from 7.5 to 15% (w/v)
applied under different voltage values between 10 to 20 kV. Flow-rate of the solution during
electrospinning process was optimized within the range of 1.75 to 3.0 ml/h. Distance between the tip and
the rotating collector was kept constant at 10 cm. Optimum conditions were determined as
electrospinning of gelatin solution of 12.5% concentration at 13 kV voltage and flow rate of 1.75 ml/h.
Electrospun conduits and membranes were treated with glutaraldehyde to avoid solubility with water
contact. Application period determined as 3 hours under vacuum. Morphology of the electrospun
products were determined by Scanning Electron Microscopy. SEM images showed that materials were
composed of nanofibers with diameters ranging between 150 nm to 800 nm.
123
Smart Polymers with Self-Assembling Ppoperties: A Challenging Contribution to the Design of
Drug Delivery Systems and Polymer Drugs
*J. San Roman, B.Vazquez, M.R. Aguilar, L. Rojo, L. García
CSIC and CIBER-BBN, Institute of Polymers, Group of Biomaterials, Juan de la Cierva 3, 28006, Madrid, Spain
The design and development of “Polymer Drugs” are one of the most attractive fields of advanced systems
for new therapeutic applications of bioactive compounds. In one biomimetic approach, these systems are
based on the preparation of polymeric chains with specific hydrophobic or hydrophilic character by the
reversible linking of bioactive compounds to macromolecular systems. This character is achieved by the
chemical reaction of specific functional groups present in the macromolecule or by copolymerization of
functionalized bioactive compounds or drugs, with specific polymerizable functions. This approach allows
very interesting designs by selecting polymerization mechanisms and composition of the active
monomers, to give high molecular weight polymers with controlled microstructure and compositions. In
a biomimetic approach we have been preparing different polymeric families with the appropriate content
and distribution of hydrophobic/hydrophilic sequences to give self-assembling systems bearing
pharmacologically active chemical structures as side residues of the main polymer chains. This allows the
fabrication of very low toxic agents for different applications, mainly directed to antiproliferative polymer
drugs, antithrombogenic nanoparticles, and specific complexing agents for cations such as calcium, zinc,
magnesium, coper of great importance in the activity of metaloproteases. As un example, we report on
the preparation and application of a methacrylic derivative of glycolipid oleyl 2-acetamido-2-deoxy--D-
glucopyranoside (OAG) and its corresponding copolymeric system with vinyl pyrrolidone VP, in order to
modify the hydrophobic character of the coupled system. The hydrolytical release of OAG from the
copolymeric drugs was tested in vitro and the antimitotic activity of OAG, its methacrylic derivative,
OAGMA, and the polymeric drugs was evaluated in cell cultures using a human glioblastoma line. In
addition, all these materials have been biologically tested using normal fibroblasts to evaluate their
biocompatibility against healthy cells. Endocytosis analysis shows that the nanoparticles infiltrate in the
cell cytoplasm and approach to the nucleus to act directly inside the cells.
124
Production of optically L(+) Lactic Acid by Using Homofermentative Lactic Acid Bacteria From Whey
A. Sofu1*, G.Güney2, F. Y. Ekinci3
1Suleyman Demirel University, Department of Chemical Engineering, Isparta, Turkey
2Suleyman Demirel University, Department of Environmental Engineering, Isparta, Turkey 3Yeditepe University, Department of Food Engineering, Istanbul, Turkey
Polylactic acid (PLA), a biodegradable polymer, has potential to replace traditional petroleum-based
plastics. However, cost-effective production of optically pure L-lactic acid is needed to achieve the full
potential of PLA. Typically, the starch-based glucose by lactic acid bacteria are (LAB) used for the
production of L-lactic acid fermentation. The disposal of whey, the liquid remaining after the separation
of milk fat and casein from whole milk, is a major problem for the dairy industry, which demands simple
and economical solutions. The lactose in whey is a source of raw materials for bioconversion. Lactic acid
can be produced industrially by chemical synthesis and microbial fermentation process. The
homofermentative LAB, mostly Lactobacilli species produce only lactic acid, cells and little else thus are
of industrial importance. Lactobacillus is by far the largest genus in LAB, and more than 125 species and
subspecies names are currently recognized. The goal of this work was to find the most suitable values of
some fermentation parameters for lactic acid production from whey by an L-lactic acid producing LAB. In
the present study, L(+) lactic acid was produced from local dairy fabricated wastes through fermentation
process and fermentation process was optimized for the maximum lactic acid yield. Process variables for
batch system were optimized for the production of lactic acid from pretreated different ratios broths by
dairy starter culture (ABT-4). The impact of 3 different media with change in volume percent of whey and
nutrient was investigated at 32 ± 0.5°C. The minimum rate of process was observed at the highest nutrient
percent (100%), at highest volume percent of whey in the medium (50%), conversion and produced.
125
Immunosuppressive Properties of Mesenchymal Stem Cells: Bench to Betside
Erdal Karaoz *1,2
1Kocaeli University, Center for Stem Cell and Gene Therapies Research and Practice, Kocaeli, Turkey
2 Kocaeli University, Institue of Health Sciences, Department of Stem Cell, Kocaeli, Turkey
In the cultivation of bone marrow cells, it has been known since 1960’s that the adherent cells on plastic
surface are stromal cells, whereas cells that are not adhesive are classified as hematopoietic cells. In
recent years, the interest in stromal cell system has steadily increased. Formerly, bone marrow stromal
cells, especially mesenchymal stem cells (MSCs), was used for the induction of hematopoesis, but later
their in vivo and in vitro differentiation features were introduced into parancymal cells of many
nonhematopoietic tissues, including muscle, cartilage, bone, nerve, liver, hearth, brain, adipose tissue,
kidney, lunge and intestine. MSCs were defined for the first time by Friedenstein, which showed the
formation of fibroblast-like adhesive cell colonies, which differentiated into bone cells and adipocytes,
after spreading of bone marrow into the medium containing fetal calf serum. In following in vivo and in
vitro studies, MSCs were described as a source of multipotent stem cells that form all three germ layers’
cells. Over the last ten years, MSCs have been thought to have important therapeutic potential because
of their self-renewal capacity and multilineage differentiation potency. On the other hand, therapeutic
effects of MSCs are believed to occur not only by direct differentiation into injured tissue but also by
production of paracrine and autocrine factors. MSCs at the injured tissue environments can promote the
secretion of a variety of cytokines and growth factors that have both paracrine and autocrine activities.
MSCs are also considered to be effective in immune system by suppressing maturation of dendritic cells
(DCs) and the functions of T cells, B cells and natural killer (NK) cells, as well as by inducing regulatory T
(Treg) cells, which enhance their regulatory effects. It has been suggested that MSCs could be useful for
the treatment and prevention of alloreactivity in a clinical transplantation setting. Considering their
immunosuppressive properties, in addition to their low inherent immunogenicity, makes MSCs an
attractive treatment option in cell and organ transplantation potentially improving the graft outcome and
eliminating a long immunosuppressive treatment regimen. The immunoregulatory effects of MSCs have
been shown in autoimmune diseases such as graft versus host disease (GVHD, osteogenesis imperfecta,
arthiritis, and encephalomyelitis.
126
Differentiation of dsDNA and ssDNA Using Conducting Polymer Coated Electrodes
F. Kuralay1,*, A. Erdem2,*, S. Abacı3, H. Özyörük3
1Ordu University, Department of Chemistry, Ordu, Turkey
2Ege University, Analytical Chemistry Department, Faculty of Pharmacy, Bornova, İzmir, Turkey 3Hacettepe University, Department of Chemistry, Ankara, Turkey
*[email protected] *[email protected]
Electrochemistry have attracted great attention for the construction of sensitive, selective, low cost and
rapid sensing platforms. Electrochemistry of nucleic acids is an important field particularly related to the
development of DNA biosensors [1,2]. The use of conducting polymers has been one of the popular
methods for electrochemical DNA detection [3,4]. In this work, poly(vinylferrocenium) (PVF+) coated
graphite electrodes were used to differentiate double-stranded DNA (dsDNA) and single-stranded DNA
(ssDNA). The electrochemical behaviors of dsDNA immobilized PVF+ modified electrode and ssDNA
immobilized PVF+ modified electrode were investigated using cyclic voltammetry (CV) and differential
pulse voltammetry (DPV).
127
Characterization of Myocardial Hydrogel Derived From Bovine Cardiac Extracellular Matrix
H. Ercan1, A. E. Elcin1, Y. M. Elcin*1,2 1Ankara University, Faculty of Science, Tissue Engineering, Biomaterials & Nanobiotechnology Lab., Ankara, Turkey
2Ankara University, Stem Cell Institute, Ankara, Turkey
Myocardial infarction is the leading cause of death of cardiomyocytes. Cardiac tissue engineering aims to
repair, replace or regenerate damaged cardiac tissue. Using extracellular matrix as a scaffold may have
significant impact in promoting cell adhesion, growth and proliferation. It can be recognized by the body
easily and degraded into nontoxic products via providing tissue specific scaffolds. Enjectable ECM matrix
offers a minimally invasive delivery route for cell therapy. Here, we evaluated the properties of the
myocardial hydrogel derived from decellularized bovine cardiac tissue. The ECM was extracted by
successive physical and chemical treatments of bovine cardiac tissue. While DNA content analyses and
H&E staining were performed to determine cellular remnants, Differential Scanning Calorymetry (DSC)
was performed to evaluate thermal properties of the native and decellularized tissue. The myocardial
hydrogel was obtained by enzymatic digestion of decellularized extracellular matrix. The gelation time
was determined by turbidimetry, and digestion protein content was evaluated by the Lowry assay. DNA
content analyses revealed a significant decrease in the DNA level of decellularized cardiac tissue. This
result was consistent with histochemistry. According to the DSC thermograms, there was almost no
difference in thermal properties between native and decellularized tissues. Turbidity was measured
spectrophotometrically. Findings demonstrated that gelation started after 10 min of incubation at 37oC.
Lowry assay results showed protein content after enzymatical digestion. Overall results indicated that the
obtained solubilized matrix may have favorable properties for tissue engineering.
128
Complex Cellular Models to Study Nanoparticle Interaction with Barrier Systems
C. James Kirkpatrick1*
1Johannes Gutenberg University of Mainz, REPAIR-lab, Institute of Pathology, University Medical Center, Germany
Nanoparticles (NPs) are of particular interest as a possible vehicle to deliver medication or biological cues.
The lung is a portal to the entire organism, so that NPs could enter the pulmonary circulation and from
there gain access to the systemic circulation and thus other important internal barriers. In the past years
we have set up coculture models of important biological barriers both of the lower (alveolocapillary (AC)
barrier) and upper respiratory tract (bronchial model), as well as of the blood-brain barrier (BBB). How
these in vitro models are established in coculture systems will be described, as well as how the uptake,
transport and storage of NPs can be investigated. Structural and functional studies are performed on these
models using immunocytochemistry, confocal laser scanning microscopy, and scanning and transmission
electron microscopy (SEM, TEM). In addition, protein analysis is possible on the upper and lower
compartments of the system (cell layer & supernatant). Functionality of the barriers is also monitored by
transcellular resistance measurements. For NP uptake across the AC barrier, various NPs based on silica
have been studied in comparison with polyorganosiloxane NPs. The influence of NP diameter and
chemistry has been investigated, and cellular uptake mechanisms appear to involve clathrin- and caveolin-
independent pathways, for example, via flotillins. The role of surfactants, which are produced in the
alveoli, are now being studied. An immunologically relevant triple culture system has also been
established for the bronchial model by adding dendritic cells (DCs), and for the AC-barrier by adding the
macrophage phenotype, as these immunocompetent cells are important in barrier defence mechanisms.
129
Targeting of Cancer Cells with Antibody Conjugated Superparamagnetic Iron Oxide
Nanoparticles
L.Tutkun1, E. Arat2, M. Turk3, T. Kutsal4*
1,4 Hacettepe University, Chem.Eng.Dept. and Bioeng. Div., Beytepe, Ankara, Turkey
2 Kırıkkale University, Biology Department, Yahsihan, Kırıkkale, Turkey 3 Kırıkkale University,Bioengineering Department, Yahsihan, Kırıkkale, Turkey
Nanoparticular systems are providing a useful toolkit for the building of nanoscale vectors for
biomonitoring and delivery of therapeutic agents in cancer diagnostics and therapy. In order to improve
their use they are usually modified by antibodies and aptamers. In this study, fluorescent dye-labeled anti-
EGFR monoclonal antibodies were immobilized onto superparamagnetic iron oxide nanoparticles to
target EGFR-positive MDA MB 231 breast cancer cells. Ostrogen receptor-positive human fibroblast cells
were choosen as a control. Monoclonal antibodies were treated with breast cancer cells in vitro.
Quantification of cellular proliferation, viability and cytotoxicity analysis were performed by WST-1 test.
Flow cytometry and real time cell analysis data were also evaluated. Fluorescent microscopy images
clearly showed that antibody conjugated superparamagnetic iron oxide nanoparticles were successfully
targeted to breast cancer cells.
The authors thank Scientific Research Agency, University of Hacettepe, (Project Number: 013 D06 602
001) for its support.
130
Plasma Proteins vs Extracellular Matrix Proteins in Cell - Material Interaction
1L. Mikhalovska
1University of Brighton, School of Pharmacy and Biomolecular Sciences, Brighton, UK [email protected]
Cell adhesion to the artificial materials occurs through the proteins bound to the material surface. In the
present study behaviour of human pulmonary microvascular endothelial cell (HPMEC-ST1.6R) on the
coatings which mimic natural substrates in the wound has been studied. Materials, such as stainless steel
(St), titanium oxide (TiO), and carbon (D) vs. cell culture treated polystyrene (Pst) conditioned with pure
human plasma proteins and human plasma were investigated. Fibrinogen (Fg), fibronectin (FN), human
serum albumin (HSA), gelatine (G), thrombin (Thr) and human plasma (Pl) in the range of concentration
0.01 up to 100% were used for coatings. Adhesion, proliferation and cytosceleton development of HPMEC-
ST1.6R cell on the coated materials were studied.
It was shown that FN, Fg, and gelatin coatings support the adhesion and proliferation of HPMEC-ST1.6R
cell on all materials, however the intensity of adhesion was dependent on both coating and the original
substrate. Materials with different ability for protein adsorption such as St, TiO and D showed the different
pattern for cell adhesion and growth after they were pre-conditioned with either pure proteins or human
plasma dilutions. SEM and calcein-stained cell images showed the well spread cells with developed
cytoskeleton on FN, Fg and gelatin coatings. Thrombin did not influence cell adhesion. Unexpected result
was obtained with human plasma coatings, where cell adhesion and growth were severely inhibited by
neat and 10% diluted plasma. The degree of inhibition varied between materials and the most apparent
inhibition of cell adhesion was seen on the polystyrene plastic with round undeveloped cell cytoskeleton.
The obtained results show that the same protein adsorbed to the different materials could be seen by the
same cell in a different way because of conformational changes in protein at the interfaces after
adsorption. It was also discovered that coating of cell culture polystyrene with human plasma in the range
of concentration from 100% to 10% showed very strong inhibiting effect on HPMEC-ST1 adhesion and
growth.
131
Molecular Biomimetics Pathways via Chimeric & Heterofunctional Peptide Probes for Molecular Recognition & Sensing
M. Sarikaya
GEMSEC, Genetically Engineered Materials Science and Engineering, Depts of Mater Sci.& Eng., Chem Eng,
and Oral Health Sci., University of Washington, Seattle, WA 91895, USA
[email protected], http://www.GEMSEC.washington.edu
Genetically Engineered Peptides for Inorganics (GEPI) are ubiquitous biomolecules, with a broad
fundamental and practical interests due to their capability for the functionalization of solids and
their use as molecular linkers, erector sets and assemblers as well as tiny enzymes to synthesize
nanosolids in molecular-technology and -medicine. Further refining combinatorial mutagenesis
approaches, e.g., cell surface and phage display libraries, adapted from the principles of drug design,
our laboratory has been experimentally selecting 100s of solid-binding peptides for a variety of
metals (Au, Pt, Au, Ti), oxides (ZnO, ZrO2), insulators (Al2O3, BN), semiconductors (GaN, MoS2, WSe2),
and minerals (HAp, Quartz, Calcite, diamond, and graphite). Unlike any other synthetic or biological
linkers, GEPIs have specific material- on-covalent
bonds to solids. To accelerate the directed evolution process, we have also established
bioinformatics methods and de novo designed multifunctional peptides in chimeric constructs.
Despite their short sequences (7-14 AA) and, hence, intrinsically disordered structures in water, the
versatility of these peptides stem from their predictable folding conformations, specific to a given
solid surface with known physico-chemical characteristics. More recently, we have developed
rational approaches to address, exclusively, the peptide-solid and peptide-peptide molecular
interactions (while bound to a surface) of a given GEPI via point and domain mutations. Based on
the understanding of the fundamental surface phenomena, novel approaches allows us to construct
peptide-enabled hybrid nanostructures with addressable chemical or physical functions and, with
extension to sensing and molecular and nanoscale recognition. We will discuss latest developments
in designing chimeric and heterofunctional peptide constructs, augmented by MD and QM
computational modeling and present examples of device architectures in environment, chemistry,
energy, and medicine (disease) implementations including graphene-FET based bionanosensors,
proto-biomieralization for cell-free tissue regeneration, and bioelectronics. The project funded by
NSF-MRSEC (DMR 0520567) and NIH-NCI (T32CA138312) Programs.
132
Biocompatibility Tests of Titanium Alloy’s That Used in Vertebral Surgery with Radiolabeling
Method
H. M. Soylu1, O. A. Ersoz2, F. Y. Lambrecht2,*
1Ege University, Inst. Of Graduate Studies in Science, Biomedical Technologies Div., Bornova, Izmir, Turkey
2Ege Üniversitesi, Inst. Of Nuclear Sciences, Nuclear Applications Div., Bornova, Izmir, Turkey
The purpose of this study was to investigate the bacterial adherence to the surfaces of titanium alloys and
polyether ether ketone (PEEK) discs which were processed with different tecniques using radiolabeling
method. E.Coli was labeled with 99mTc and their radiolabeling yields were calculated as 99,99%. After the
labeling procedure, metal discs (3mm×16mm) and peek cages were treated with microorganisms.
Efficiency of labeled microorganisms adhered on materials surface was measured by Cd(Te) detector. It is
observed that processed samples shown high biocompatibility by comparing with control sample.
133
A Communication Device for Patients on a Dental Chair Unit
E. Jafaribarani1, M. Pehlivan2*, F. Hamidnia1, S. Abdijodaghieh1
1 Ege University, Graduate School of Science, Biomedical Technologies, Izmir, Turkey 2 Ege University, Faculty of Medicine, Department of Biophysics, Izmir, Turkey
A patient is usually experience difficulty to express his situation sitting on a dental chair unit while the
mouth was open and the dentist was in practice with noisy instruments. We describe a new
communication device and a method between the patient and the dentist which is very simple to use. The
device consists of hand piece which is a tennis ball sized air filled balloon in a pouch, miniature pump and
electric valves to control the pressure level in the hand piece, a microcontroller (PIC 16F877A) to read
pressure level, to control pump and valves and to communicate with the computer, and a computer to
control the system, to display the measured values and to give out the pre-recorded vocal expressions.
The pressure level of the hand piece is calibrated according to the maximum gripping pressure of the
patient. Level and slope of air pressure variation in the hand piece is continuously monitored by the
microcontroller through a pressure sensor. Pressure level and slope scaled to different vocal expressions
of pain or anxiety such as a slight grip of hand piece will produce a voice of “I may feel pain”. The system
has another optional feature to divert the patient. A game with light emitting diodes (LED) is prepared
and installed in microcontroller system. The patient follows the light color or light position by gripping the
hand piece in correct pressure level or speed.
Patient pleasure and comfort evaluated by questionnaire. Preliminary results show that the method is
useful especially for children sitting on dental chair unit.
134
Developing Novel Three Dimensional 3D Osteosarcoma Models with Using Cancer Stem Cells
M. Anil1, S. Ozturk2, I. Deliloglu Gurhan1,3, S. Vatansever4, M. Kivanc4, A. Sendemir Urkmez *1,3
1Ege University, Graduate School of Natural and Applied Sciences, Department of Bioengineering, , Izmir, Turkey 2Ege University, Graduate School of Natural and Applied Sciences, Department of Biomedical Technology, Izmir,
Turkey 3Ege University, Faculty of Engineering, Department of Bioengineering, Izmir, Turkey
4Celal Bayar University, Faculty of Medicine,Department of Histology and Embryology, Manisa, Turkey
Traditional two-dimensional (2D) cell culture system was a convenient way to study cancer cells in vitro.
But, 2D model is not successful to mimic the tumor structures such as cell-cell communication and cell-
extracellular matrix (ECM) interactions, which plays a key role in cancer tissue. The three-dimensional (3D)
cell culture system in vitro is closely related to tumorigenicity in vivo and the gap between 2D system and
tumors in vivo. 3D tumour models might serve as useful tools for anti-cancer therapeutics and cancer
stem cells (CSCs) research. Cancer stem cell (CSC) population is a small subset of cells within a tumour
with high tumoregenicity and metastase potential. It has been reported that CD133 (+) cells from
osteosarcoma-stabilized cell lines possess stem cell features, such as differentiation potential and high
proliferation rate. The aim of this study is devoloping different three dimensional (3D) osteosarcoma
models and investigation features of this subpopulation for each model. In this study, osteosarcoma cell
line (SaOs-2) was used to isolate osteosarcoma stem cells (OSCs). OSCs, CD133+ cell population, were
isolated from osteosarcoma cells by MACS (Magnetic-activated cell sorting) technique. As 3D models,
micro tissues produced by using 3D Petri DishTM and cell cultivation in bacterial cellulose scaffolds were
used. 3D morphologies of OSCs were examined by scanning electron microscopy (SEM). OSCs cultivated
by using different 3D cultivation methods were investigated with regards to expression of Ki67, CD133,
OCT4, SOX2 by immunocytochemical analyses and qPCR for evaluation cell properties after cultivation.
The study is seen as an introduction to develop a novel 3D tumour model to study CSC behaviour and
tumourigenesis in vitro. Developing a 3D tumour model, which is originated from CSCs might be an
accurate, fast and economical alternative to animal experimentation to study behaviour of CSCs and
develop strategies for cancer treatment.
This work was supported by TUBITAK through COST project (113M243).
135
Biofilm Dispersal and Its Impact in Bacterial Virulence
N. Cerca*
University of Minho, CEB - Centre of Biological Engineering, Campus de Gualtar, 4710-057 Braga, Portugal
* Email: [email protected]
The shift between mobile or immobile physiological stages is a phenomenon widely spread amongst living
organisms. In eukaryotes, this is often associated with sexual reproduction and the production of
dispersive biological elements. In bacteria, we now call this shift between free floating planktonic or
sessile microorganisms the biofilm life cycle. A biofilm is defined as a community of bacteria attached to
a surface and surrounded by a complex extracellular matrix. Biofilms are an important topic of research
mainly due to their high resistance to antimicrobial therapy and high ability to evade the immune system.
Importantly, some harmless commensal organisms can become virulent when growing within a biofilm,
such as Staphylococcus epidermidis. Despite its clinical important, biofilm dispersal, this is, the release of
cells from the biofilm to the host, is still poorly understood. We now know that biofilm dispersal can either
have intrinsic or extrinsic origins but the implications of dispersal cells in biofilm-related infections are still
a matter of debate. In this lecture I will make an overview of the biofilm formation process, and will focus
on the characterization of biofilm-released cells and their potential impact in virulence.
136
Quantification of Biofilm-Associated Genes in Staphylococcus Epidermidis Biofilms: Its Impact in Biofilm Formation and 3D Structure
N. Lopes and N. Cerca* * Email: [email protected]
University of Minho, CEB - Centre of Biological Engineering, Campus de Gualtar, 4710-057 Braga, Portugal
Staphylococcus epidermidis is a common commensal coloniser of the human skin and is currently the most
frequent cause of biomaterial associated infections. Several studies have attempted to identify the
determinants that distinguish invasive from commensals S. epidermidis strains. Its pathogenesis is directly
related to its ability to establish multi-layered and highly structured biofilms, resistant to antimicrobial
agents. This bacterium expresses several factors that are responsible for the development of the biofilm,
including the contribution of specific factors (icaA, aap and bhp genes) in the accumulation phase.
Recently, several research groups have been trying to understand the contribution of the genes involved
in biofilm formation. Thus, the main goal was to analyse the gene expression of icaA, aap and bhp and
compare with the formation of the biofilm structure. Two S. epidermidis strains, a clinical and a
commensal were characterized at the level of biofilm formation, at different incubation times. According
to our results both strains showed an increase of biomass production overtime, revealing the importance
to use screening assays with more than 24 h of incubation. A biofilm structure analysis was also performed
to detect the presence of poly-N-acetylglucosamine (PNAG), the major component of S. epidermidis
biofilm matrix. The results revealed a higher production of PNAG only after 48 h for SECOMO034.A1.
Finally, the gene expression at two different incubation times was determined, confirming the importance
of the icaA gene in the accumulation stage, explaining the high production of biomass and PNAG. On the
other hand, the aap and bhp expression levels raised some questions about their role in the biofilm
process.
137
Biomechanical Cues Enhance Myogenesis of Adipose Derived Stem Cells
P. Yilgor Huri1*, C. A. Cook1, D. J. DiGirolamo2, W. L. Grayson1
Johns Hopkins University School of Medicine, Departments of 1 Biomedical Engineering and Translational Tissue
Engineering Center, 2 Orthopaedic Surgery, Baltimore 21231MD, USA
Adipose-derived stem cells (ASCs) are multipotent, easily accessible and abundant; therefore of great
interest to engineers of mesenchymal tissues. The major problem limiting their therapeutic use is their
low differentiation efficiency. The aim of this study was to enhance the efficiency of ASC myogenesis
through the application of uniaxial cyclic stretch which mimics the natural biophysical cues intrinsic to
skeletal muscle. Human ASCs were seeded in specialized 6-well plates with flexible membrane substrates.
From Days 3 – 21 of culture, cell monolayers were exposed to uniaxial cyclic stretch using the Flexcell®
tension system with parameters: 15% strain, 0.5 Hz, sinusoidal waveform, 1h/day (Dynamic). Control cells
were not subjected to strain (Static), or cultured on tissue culture plastic (TCP) under identical conditions.
We assessed cell morphology (phase contrast microscopy) throughout the culture period and myogenesis
was verified by RT-PCR and immuno-cytochemistry for muscle-specific markers. There were distinct
morphological differences from 1 day after biochemical induction between uninduced cells, which
proliferated randomly, and induced cells, which formed multinucleated fibers through fusion of individual
cells. ICC revealed that ASCs were able to form multinucleated myofibers while expessing muscle specific
Pax 3/7, desmin, MyoD1 and myosin heavy chain on Dynamic samples while the myogenesis on both Static
and TCP conditions were negligable. ASC myogenesis could be significantly enhanced by mimicking the
cues within the native muscle microenvironment through the application of cyclic stretch.
138
Poly (ε-lysine) Dendrons as Modulators of Quorum Sensing, and Alternatives to Conventional
Antibiotics for Pseudomonas aeruginosa Infections
R. Issa *, S. Meikle, S. James, and I. Cooper
University of Brighton, School of Pharmacy and Bimolecular Sciences, Huxley Building, Lewes Road, Brighton, BN2 4GJ, UK
Quorum sensing (QS), an intercellular signalling system in Pseudomonas aeruginosa, regulates the
expression of multiple extracellular virulence determinants. Given the rapidly expanding problem of
antibiotic resistance, interrupting QS using synthetic molecules represents a novel alternative to
conventional antibiotics. We have previously shown the potential of hyperbranched poly (ε-lysine)
dendrons, and their ability to enhance the efficacy of ciprofloxacin and reduce toxin production. In this
study, we evaluate the effects of generation 3 poly (ε-lysine) dendrons, RG3K, on the production of QS-
regulated motility, biofilm formation and exopolysaccharide production in the wild-type P. aeruginosa
strain, PAO1. Poly (ε-lysine) dendrons were synthesised using solid-phase peptide synthesis to generate
RG3K, a hyperbranched macromolecule composed of 15 lysine units and an arginine root. Under semi-
solid and aqueous environmental conditions, RG3K reduced swarming and swimming motility by 82% and
35%, respectively (P≤0.001). Using a crystal violet biofilm assay, RG3K was found to reduce PAO1 biofilm
formation in a concentration dependent manner. At 400-µM, where RG3K has no significant effects on
cell viability, biofilm formation was reduced by 80% 24h-post treatment in nutrient-rich media (P<0.001).
Microscopic analysis of these biofilms demonstrated the ability of RG3K (400-µM) to reduce microcolony
formation and attenuate the production of exopolysaccharides. Furthermore, RG3K was found to reduce
QS-controlled LasA protease activity to below the detection threshold when added after 3h of growth
(P<0.001), and decrease pyocyanin production by 86% (P=0.006). Our findings therefore demonstrate the
potential of hyperbranched peptide-based QS-modulators as a novel alternative to conventional
antibiotics.
139
Molecular and Functional Characterization of Pichia Pastoris MIG1 and MIG2 Genes
S. Yılmaz1, H. Yıldız and M. İnan1*
1Akdeniz University, Department of Food Engineering, Antalya, Turkey
The methylotrophic yeast Pichia pastoris is widely and successfully used as a host system to produce
recombinant proteins for a variety of applications. The rising popularity of the system could be attributed
to several characteristics, including the ability to perform many eukaryotic post-transcriptional
modifications, and the capability to produce heterologous proteins at high level. In the P. pastoris system,
the expression of foreign genes is usually driven by the promoter of the alcohol oxidase gene I (AOX1)
which encodes the first enzyme in the methanol utilization pathway. Under a very strict control, the AOX1
promoter is highly induced by methanol and repressed by glucose and ethanol. In this study, the
mechanism of catabolite repression of P. pastoris has been studied. For this purpose, the molecular and
functional characterization of the MIG1 gene, which is determined to have the key role in catabolite
repression mechanism for S. cerevisiae and other yeasts, were done. Single (mig1, mig2) and double
mutant (mig1mig2) P. pastoris strains have been obtained by inactivation of MIG1 and MIG2 genes.
Their growth characteristics and alcohol oxidase enzyme (aox) activities were examined in media
containing glucose, glycerol and methanol mixtures. Aox activity has not been detected in media
containing glucose/methanol with all the strains tested. About 30% and 50% aox activity was detected in
mig2 and mig1mig2 strains in glycerol/methanol media compared to that of wild-type strain in
methanol media, respectively. Overall results suggested that the PpMig1 and PpMig2 proteins play a role
in regulation mechanism of AOX1 promoter in glycerol containing media.
140
Molecularly Imprinted Composite Cryogel Column for L-Phenylalanine Separation
S. Akgonullu, H. Yavuz, A. Denizli
Hacettepe University, Department of Chemistry, 06800, Ankara, Turkey
E-mail: [email protected]
Amino acids are the main structural components of proteins and enzymes. Chiral separation of amino acid
enantiomers is of great importance in diverse fields, such as life science, pharmaceuticals, agrochemicals,
foods, feeds, perfumes, and so forth since amino acid enantiomers show different physiological activities
depending on their absolute configurations. Molecular imprinting is an alternative method that has been
developed to enable the selective removal of a target molecule from a mixture containing many ligands.
During polymer synthesis, a material is created that contains multiple binding sites shaped by a template
(the target). The resulting materials are commonly called molecularly imprinted polymers (MIPs).
Macroporous polymeric materials have been extensively studied in biotechnology and biomedical
engineering. Cryogels are a very good alternative to bioseparation with many advantages including large
pores, short diffusion path, low pressure drop and very short residence time. But, due to the existing of
large pores within the cryogel, the adsorption capacity for the biomolecules is low. In actual bioseparation
processes, it is of great importance to improve the binding capacity of supermacroporous cryogel.
Therefore, particle embedding would be a useful improvement mode to use in the preparation of novel
composite cryogels for increasing surface area. In this work, L-Phe imprinted composite column in the
cryogel form were prepared by using molecular imprinting technique for the recognition of L-Phe. N-
Methacryloylamido-(L)-Phenylalanine (MAPA) and L-Phe was used as functional monomer and template,
respectively. L-Phe imprinted composite cryogel column were characterized by Fourier transform infrared
spectroscopy (FTIR), surface area measurement (BET), scanning electron microscope (SEM).
Chromatographic L-Phe recognition performance of the L-Phe specific composite cryogel column was
investigated under different adsorption conditions. In the last step, selectivity studies were performed in
the presence of competitor amino acid and the reusability of the cryogel membranes was investigated.
141
Fabrication of Scaffolds from Bioactive Glass for Bone Tissue Engineering
S. YUCEL1*, A.C. OZARSLAN1, S. BEKLEVICUYLASI1, B. KARAKUZU1
1Yildiz Technical University, Faculty of Chemical and Metallurgical Engineering, Department of Bioengineering, 34220, Esenler/İstanbul
E-mail: [email protected]
Bone tissue engineering is a rapidly developing branch of science, which provides defective bone tissue
repair, replacement or re-enabling production aid of a biodegradable and biocompatible tissue scaffold.
With this approach, one of the shortcomings of the healing process can be shortened. The tissue scaffold,
one of the three main components of bone tissue engineering and the key component of bone healing,
mimics bone morphology and acts as a mold for the desired cellular response. Bioactive glasses are
biocompatible, bioactive, osteoconductive and osteoinductive tissue scaffold materials which exhibit
excellent performance in bone tissue regeneration. When bioactive glasses are placed in a human bone
tissue, they connect easily with tissues via formation of hydroxyapatite on the surface layer. Also,
bioactive glasses provide the cellular activity. However, to improve properties of bioactive glasses for
bone production, some ions may be added to the chemical composition of glasses. Tissue scaffold
properties can be contributed by forming the bioactive glass tissue scaffolds with polymers to produce
composite structures. In this study, the generation and characterization of three-dimensional tissue
scaffolds for bone regeneration is aimed by using commercial silica-based 45S5, 46S6 and silica-based rice
hull ash 45S5, 46S6 samples. Tissue scaffolds were manufactured using polymer foam replica method. The
produced tissue scaffolds were coated with gelatin using the polymer coating method in order to develop
bioactive behavior and mechanically enforce. After that they were characterized by Fourier transformed
infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). As a result of FT-IR analysis, any
undesirable chemical bond formation was observed. In the SEM analysis, pore formation was illustrated
clearly. Gelatin-coated tissue scaffolds, have better mechanical properties than which were not coated.
The results showed that three-dimensional polymer / bioactive glass composite tissue scaffolds are
potential candidates for bone tissue engineering applications.
142
Effect of Low Level X-ray Radiation on Biosynthesis of Goldnanoparticles by Streptomyces
Bacteria
F. Saghatchi1, M. Salouti2*, GH. Jafari3, J. Taran4
1Zanjan University of Medical Sciences, Faculty of Paramedical and Health Sciences, Department of Radiology, Zanjan, Iran
2Zanjan Branch, Islamic Azad University, Biology Research Center, Zanjan, Iran 3Zanjan University of Medical Sciences, Faculty of Paramedical and Health Sciences, Department of Microbiology,
Zanjan, Iran 4Zanjan University of Medical Sciences, Faculty of Paramedical and Health Sciences, Department of Biochemistry,
Zanjan, Iran
In this study, we used low dose X-ray radiation as the stimulating agent for enhancing the biosynthesis
rate of gold nanoparticles production by Streptomyces bacteria. The soil samples collected from a lead
mine were diluted and spread on starch casein agar to isolate the genus Streptomyces bacteria. Then, the
bacterial culture was grown in MGYP broth medium. After 48 h incubation, the medium was centrifuged
and each 3 gr of obtained biomass was suspended in a 500 mL Erlenmeyer flask in 4 groups. We exposed
the bacteria to four different doses of X-ray radiation from low to high levels, separately. Then, the
exposed bacteria were treated by 50 ml HAuCl4. The mixtures were incubated in an orbital shaker for 72
h. The preliminary detection of gold nanoparticles formation was monitored by observing the color
change of the mixture and the quantity measurement was performed by atomic absorption spectroscopy.
In conclusion, we found that low dose X-ray radiation can stimulate the formation of gold nanoparticles.
143
Polysaccharide Hydrogels in Nanobiotechnology
R. Barbucci *1, M. Uva 2, L. Mencuccini 2 , G. Rocchigiani 2 , A. Atrei 1,2
1Interuniversity Research Centre for Advanced Medical Systems (C.R.I.S.M.A), Siena, Italy 2University of Siena, Department of Biotechnology, Chemistry and Pharmacy, Siena, Italy
The combination of polymeric hydrogels and magnetic nanoparticles (NPs) constitutes a novel class of
functional composites as drug delivery system keeping both hydrogel and magnetic NP properties.
Hydrogels represent ideal drug delivery systems since the duration of release and delivered dose can be
controlled, moreover other intrinsic characteristics of hydrogels are the low cost, excellent
biocompatibility, non-toxicity and the possibility of chemical functionalization. On the other hand
magnetic NPs present the capability to be manipulated using magnetic field. Thanks to this property, the
release of the drug from the magnetic hydrogel, can be modulated by means of external magnetic fields,
allowing for the delivering directly at the site of the cancer, maximizing the therapeutic effect and
minimizing toxicity to healthy tissues. The aim of this study is to obtain carboxymethylcellulose hybrid
hydrogels with magnetic nanoparticles (NPs) as cross-linkers (CMC-NP) and test these as systems for the
controlled release of an anticancer drug under the application of alternating magnetic field (AMF). The
hybrid hydrogels were chemically characterized as well as their viscoelastic and magnetic properties. Their
morphological analyses were performed using a Zeiss FESEM (Field-Emission Scanning Electron
Microscope). The effects of the magnetic hybrid hydrogel on the proliferation and differentiation of
osteoblast were investigated. Finally the hydrogels were tested as drug controlled delivery system for
Doxorubicin (DOXO) by applying an alternating magnetic field with a frequency of 40 Hz and a magnetic
induction of 2 mT. When the AMF is applied on the system the amount of DOXO released from the CMC-
NP is greater than that released by the same CMC-NP not exposed to the magnetic stimuli. As the NPs are
covalently linked to the network of the gel, when NPs follow the oscillation of the magnetic field the
polymer chains twist with the consequent formation of more open structures and hence pores of larger
dimensions, that facilitate the release of DOXO molecules. The effect of the AMF on the hydrogel
morphology and thus on the drug release occurs only when the NPs are covalently bonded to the polymer
network.
144
Advanced Micro Bio reactor system for high-throughput parallel cell line selection and
process development in CHO cells for MAb production
von Strandamnn, Ralph1
1TAP Biosystems, Royston, United Kingdom
In 2010 a multi-parallel bioreactor mimic was launched for the to improve cell line selection data, in order
to identify the most suitable strains for MAb production in Bioreactors. The existing technology of parallel
shake flask processes had a number of recognized shortcomings, such as high level of manual
intervention, lack of pH control and a low confidence in assessing shear stress response by cell lines.
However the alternative technology of bench-top bioreactors did not allow sufficient throughput to
evaluate large numbers of cell lines. This posed the problem of moving forward with either insufficiently
characterized cell lines, or dropping the most suitable sell lines at an early stage due to poor performance
in untypical shake flask environment. In this presentation we describe the ambr system which attempts
to provide better quality data for more cell lines. In addition we will look at how initial process
development experiments have been carried out on the same platform. Whilst it is always difficult to
present results from actual work done by commercial companies due to confidentiality considerations,
we will show some of the data which have been released into the public domain by manufacturing
companies.
145
Electrochemical Detection of Pathogenic Bacteria Using Bacteriophages at a Single-Use Graphite Electrodes Modified with Gold Nanorods
F. Moghtader1, G. Congur2, A. Erdem2* , E. Piskin1*
1 Hacettepe University, Chemical Engineering Department, Bioengineering and Nanotechnology
and Nanomedicine and Divisions and Biyomedtek/Nanobiyomedte, Ankara, Turkey 2Ege University, Faculty of Pharmacy, Analytical Chemistry Department, Izmir, Turkey
Monitoring food and water quality has been argued as the most important priority towards national and
international health and safety issues with global emphasis on rapid and early detection of pathogen
contamination especially in food and water. There has been a continuous growing interest to develop new
methods and devices that would provide highly reproducible and sensitive easy to use sensing assays.
Here, an electrochemical biosensor system using bacteriophages as specific probes to detect target
bacteria at a single-use graphite electrodes modified with gold nanorods. T4-bacteriophage
against Escherichia coli (E.coli) as the model gram-negative bacteria was selected as an example to
develop the protocol. A non-pathogenic strain of E.coli was used for isolation and multiplication of T4
phages. Phage dispersions containing different concentrations of phages (105–108 PFU/ml) were prepared
by diluting an initial phage stock prepared prior to use. Gold nanorods (AuNRs) were synthesized by a
rather conventional protocol and characterized by different techniques. Single-use pencil graphite
electrodes (PGEs) were modified by AuNRs. The modification of PGE surface with AuNRs increased
sensitivity significantly. After AuNR modification onto PGE surface, T4 phages were immobilized onto the
surface of those modified PGEs. The electrochemical characterization using electrochemical impedance
spectroscopy (EIS) was firstly performed to present the successful AuNR and bacteriophage modification
onto the PGE surface. Selective and sensitive detection of the target bacteria (E.coli) was demonstrated
by using EIS. Selectivity of the T4 phages against E.coli was approved in the test where bacterial
suspensions containing also other non-target bacteria (S.aureus) were used.
146
Synergistic Antifungal Effects of Quince Leaf’s Extracts and Silver Nanoparticles on Aspergillus niger
H. Alizadeh1*, M. Rahnema2, Sh. Nasiri Semnani, M. Ajalli3, N. Javar3, F. Moghtader4
1 Islamic Azad University, Zanjan Branch , Young Researchers and Elite Club , Zanjan, Iran 2 Islamic Azad University, Zanjan Branch, Biology Research Center, Zanjan, Iran
3 Islamic Azad University, Zanjan Branch, Department of Microbiology, Zanjan, Iran 4 Hacettepe University, Chemical Engineering Department, Bioengineering and Nanotechnology and
Nanomedicine Divisions and Bioengineering R&D Center - Nanobiyomedtek, Ankara, Turkey
Invasive fungal disease represents a major threat to life in immunocompromised patients and is now one
of the most common causes of infection in this group. There is a limited range of antifungal agents
available to treat disease caused by Aspergillus including the polyenes, flucytosine, azoles and more
recently the echinocandins. Therefore it is necessary to find new ways of treatment for Aspergillus niger.
The aim of this study was to investigate the synergistic antifungal effects of Quince leaf’s extracts and
silver nanoparticles on A.niger in vitro. The ethanolic and acetonic extracts of Quince (Cydonia oblonga)
leaf’s and silver nanoparticles prepared. Antifungal effects of extracts and silver nanoparticles against A.
niger investigated by agar dilution method. Then minimum inhibitory concentration (MIC) and minimum
fungicidal concentration (MFC) determined by the broth macro dilution method. Then synergistic effect
was studied between the most effective plant extract with silver nanoparticles. The results showed that
the C. oblonga extracts and silver nanoparticles can inhibit the growth of A. niger. Ethanolic extract was
more effective extract that has antifungal activity against A. niger and synergistic activity observed
between ethanolic extract of Quince’s leaf and silver nanoparticles against A. niger. Ethanolic extract of
Quince’s leaf and silver nanoparticles has synergistic antifungal effect against A. niger and can be effective
in controlling of A. niger.
147
Effect of Intraperitoneal Injection of Colloidal Silver Nanoparticles on Biochemical and Hematological Parameters in Mouse
H. Alizadeh1, H. Hamzehei2, M. Rahnema3*, N. Javar3, F. Moghtader4
1 Islamic Azad University, Zanjan Branch, Young Researchers and Elite Club, Zanjan, Iran
2 Zanjan University of Medical Sciences , School of Medicine, Medical technology Research Center, Zanjan, Iran
3 Islamic Azad University , Zanjan Branch Biology Research Center, Zanjan, Iran 4 Hacettepe University, Chemical Engineering Department, Bioengineering and Nanotechnology and
Nanomedicine Divisions and Bioengineering R&D Center - Nanobiyomedtek, Ankara , Turkey
Recently silver nanoparticles were used extensively in various fields, especially in the control of bacterial
infections. But the toxicity of silver nanoparticles caused very concern in the use of these materials in
various fields of industry and medicine. The aim of this study was clarify some of these ambiguities and
investigation the effect of intraperitoneal injection of colloidal silver nanoparticles on mouse biochemical
and hematological parameters. In this experimental study, 21 adult female rats were randomly divided
into 7 groups. The mice were weighed. Group 1 was sham. Control group 2 and group 3 to 7 experimental
groups were treated respectively with 5, 10, 20, 40 and 80 ppm of silver nanoparticles. Mice treated for
10 days. On the eleventh day the rats were killed by diethyl ether anesthesia. Blood samples were taken
from the heart. Then the biochemical and hematological parameters and lactate dehydrogenase (LDH)
levels evaluated. The results showed no significant changes in biochemical factors except triglycerides
(TG) that showed a significant decrease in the high concentration of silver nanoparticles. Significant
changes were observed at concentrations higher than 20ppm of silver nanoparticles in blood parameters
includes: Reduce the amount of white blood cells, increasing of platelets, Slight decrease of hemoglobin
and hematocrit percent. At 80 ppm concentration of silver nanoparticles the serum level of lactate
dehydrogenase fell sharply. Intraperitoneal injection of silver nanoparticles in mice does not affect
biochemical factors but of high concentrations of silver nanoparticles can affect blood factors.
AUTHORS
1 Coban 43 Aydogan 85 Şardan 2 Sengiz 44 Akhmetova 86 Chanishvili 3 Migliaresi 45 Kues 87 Ghudumidze 4 Illsley 46 Sahin 88 Sousa 5 Taykoz 47 Utkan 89 Ozkan 6 Cohn 48 Çimen 90 Demir 7 Wang 49 Nasseri (Nanobiotechnology
2014) 91 Yucel
8 Senyurek 50 Seymen (Nanobiotechnology 2014)
92 Didarian
9 Karatas 51 Seymen (Biomed 2014) 93 Harbottle 10 Usta 52 Ates 94 Brown 11 Aydinlioglu 53 İnan 95 Kayaalp 12 Akdur 54 Türkaydın 96 Ari 13 Gok 55 Elçin 97 Tekay 14 Oksuzoglu 56 Surucu 1 98 Bulmuş 15 Aktas 57 Tuncel 99 Missirlis 16 Demirel 58 Çalış 100 Ekinci 17 Eksin 59 Koc 101 Yang 18 Ozgur 60 Demirkan 102 Ahi (Biomed 2014) 19 Kara 61 Can 103 Mahmoudi Azar 20 Congur 62 Oktar 104 Erdem 21 Karadeniz 63 Sener 105 Çetin 22 Vargel 64 Shikhaliyeva 106 Hasturk 23 Tuzlakoglu 65 Kesenci 107 Eğri (Nanobiotechnology 2014) 24 Makalatia 66 Akçapınar 108 Salimi 3(Biomed 2014, 2) 25 Alini 67 Miertus 109 Dibekkaya 26 Lacin 68 Salouti 110 Haberal (Nanobiotechnology
2014) 27 Sardan 69 Ghanaati 111 Erdem (Nanobiotechnology 2014) 28 Hasirci 70 Rigvava 112 Çetin (Nanobiotechnology 2014) 29 Salimi 1 (Nanobiotechnology
2014) 71 Yilmaz 113 de la Vega
30 Odabas 72 Guven 114 Ozturk 31 Ucar 73 Arat 115 Mottaghy 32 Haberal (Biomed 2014) 74 Allan 116 Cimen 33 Saylan1 75 Kökdemir 117 Özden 34 Salimi 2(Nanobiotechnology
2014) 76 Ahangari 1 118 Ozer
35 Ahi (Nanobiotechnology 2014) 77 Ozdemir 119 Ulusu 36 Ebrahimi 78 Tekay (Biomed 2014) 120 Onaral 37 Yıldırım 79 Babur 121 Allan (Nanobiotechnology 2014) 38 Kumar 80 Unsal 122 Inci 39 Dana 81 Sasmazel 123 Bölgen 40 Norouz Dizaji 82 Cooper 124 B. Nasseri (Biomed 2014)
41 Eğri (Biomed 2014) 83 Karaoz 125 Ercan 42 Sofu 84 Karatas 126 James
127 San Roman 133 Kuralay 139 Tutkun 128 Mikhalovska 134 Cerca (Nanobiotechnology 2014) 140 Akgonullu 129 Sarikaya 135 Lopes 141 Yucel 130 Soylu 136 Huri 142 Saghatchi 131 Jafaribarani 137 Issa 143 Barbucci 132 Anil 138 Yilmaz 144 Strandamnn